What are the status codes of your header checker test? Are you using multiple redirect strings (hopefully not)? Did you change anything else?

Old Domain: SERVER RESPONSE: HTTP/1.1 301 Moved Permanently
New Domain: SERVER RESPONSE: HTTP/1.1 200 OK

The redirection is on the .htaccess file.

Nothing else change, same directory structure and url rewrite

You rewrote all of your URLs to the new domain? Ex: olddomain.com/page.html -> newdomain.com/page.html.

change links on all my other sites and all social networks.

This is the one I wouldn't have done if you did an old page to new page mod-rewrite.

In effect you removed all the old links in favor of new links.

It will most likely work itself out in 3 to 4 monhs.

How big is the site?

As fathom said (and if Google is to believed), then the effect of your link profile will come back in a few months once Google adjusts. You've traded a likely long term 85% loss of power on IBLs for an initial hit, with a full recovery (AFAIK all of this is based on answers by Google reps to questions asked of them).

Without mentioning any specifics (forbidden by the charter) would you be prepared to provide more information about exactly what you've done? For instance:
- did you change the geo-targeting of the domain (i.e. were you .com / .net / .biz / .info before and are now .co.uk / .de / .fr etc
- does either the old domain or new domain contain keywords that (used to) send you traffic
- do you have important keywords that you used to rank for and now don't, or does your traffic come from multiple pages and keywords

Be as specific as you can without giving away any identifying information :)

How big is the site?

- About 70K daily visitors and over 150K daily page views

did you change the geo-targeting of the domain (i.e. were you .com / .net / .biz / .info before and are now .co.uk / .de / .fr etc

- Was 12345-6789.com and now 23456789.com Remove de dash and short the name

does either the old domain or new domain contain keywords that (used to) send you traffic

- Possible, but was a bit more specific. New domain should be even better, more broad (at leas that's what I think) Think about like a house. Instead of just livingroom-xxxx.com, now is housexxxx.com .

do you have important keywords that you used to rank for and now don't, or does your traffic come from multiple pages and keywords

- Multiple pages and keywords


Thank you for all your comments guys. I just hope I didn't screw up my whole business, plans and life for an stupid domain change.

How big is the site?

About 70K daily visitors and over 150K daily page views

Sorry, I was not clear enough. What I meant is - how many pages does the site have and how many pages are indexed by Google? Because this will influence how quickly the rankings return.

This is what fathom and FranticFish above were talking about.

Lets see what Google is seeing:

• Google discovers the new site and starts to spider like crazy (Google is always much more focused on crawling new links than on re-crawling existing)
  
  
• Assessing new pages, they are initially probably found to be duplicates of pages on your old domain (because unless Google recrawls a page from your old domain, Google does not know that the page is now redirecting to this new URL
  
  
• By crawling your other sites, Google sees that links that pointed to pages on your old domain now point to a different, new domain
  
  
• By losing link juice, pages on your old domain have lower page rank and lower page rank is likely to influence how often they are crawled. So by diverting links a bit too soon, you have weakened your old domain and possibly also reduced crawling budget. This is likely to result in two things:
  
  1. it may take longer for all of the URLs from the old site to be re-crawled (and you need this in order for Google to see 301)
     
  2. these pages are now ranking worse as the old domain is weakened. So they drop in ranking, but the new domain is not yet strong enough to take its place as Google has not yet fully digested this was a domain move.

To be honest, I think you will have to sit it out and wait for the site to recover, and depending on the number of pages on the site, it may take up to 6 months or sometimes even longer for Google to digest the changes.

There are few things you could try though (if you haven't already):

• Add both sites to the same Google Webmaster Tools account, verify both and execute "Site move" option in there.
  
  
• Temporarily, make sure the same sitemap.xml can be accessed under both domain names (do not redirect). Getting the example-old.com/sitemap.xml with URLs in there for example-new.com/sitemap.xml is a strong hint. This can be removed once the site move is fully digested
  
  
• make sure robots.txt is not redirecting, i.e. allow robots.txt to be accessed under old site name, or even better, have two robots.txt and internally rewrite request for the old site robots.txt to serve the content from a different physical file, where you do not block anything and where you allow Google to access old site URLs in order to see redirect
  
  
• monitor the number of indexed pages from the old site, over the time they should be dropping
  
  
• select a handful of pages whose ranking you want to monitor, as a test. Search for a unique and exact phrase from the page (in the quotes) and initially both pages will be returned in SERPs. Make note of the order which domain is first listed and which is second. Also check the ranking for the main keywords (unquoted) for this page. At the point when only one result is returned for the quoted text (presumably the old domain dropped off the index), check whether the new domain's rankings improved for the main keywords. If it is, it is a good sign.

I would also tripple check that there are no (and have not been) technical errors with regards to the site move execution.

Sorry, I was not clear enough. What I meant is - how many pages does the site have and how many pages are indexed by Google? Because this will influence how quickly the rankings return.

413,180 URLs submitted
314,610 URLs indexed (about the same as the old domain)

Add both sites to the same Google Webmaster Tools account, verify both and execute "Site move" option in there

. Yes both site are in the same account

Temporarily, make sure the same sitemap.xml can be accessed under both domain names (do not redirect). Getting the example-old.com/sitemap.xml with URLs in there for example-new.com/sitemap.xml is a strong hint. This can be removed once the site move is fully digested

make sure robots.txt is not redirecting, i.e. allow robots.txt to be accessed under old site name, or even better, have two robots.txt and internally rewrite request for the old site robots.txt to serve the content from a different physical file, where you do not block anything and where you allow Google to access old site URLs in order to see redirect

monitor the number of indexed pages from the old site, over the time they should be dropping

I used the instruction from Google Webmaster Tools to transfer the domain ( [support.google.com...] ). The instructions asked to add a redirection on my old site to complete the transfer.

Looks like Google it's indexing my pages, but I think the problem is the page ranking. At this point, I'm planning to just suck it up and keep working on my site like I have been doing for years (adding more content, content, content).

Also, I have been considering removing the redirections from my old domain, and use a canonical tag to the new domain. Do you think it' a good idea?

413,180 URLs submitted

This is a big site. It will take Google some time to digest the change.

At this point, I'm planning to just suck it up and keep working on my site like I have been doing for years (adding more content, content, content)

Yes, this is a good approach.

The instructions asked to add a redirection on my old site to complete the transfer.

Yes, but robots.txt should not redirect. This is also clear in instructions, as there it says that the old site robots.txt should not have anything blocked, implying this robots.txt is a different one to the new site robots.txt. So check whether, when you request robots.txt from your old site, whether it is redirecting or not and if it is, remove the redirect and serve a different robots.txt for your old site, allowing googlebot the access.

Also, I have been considering removing the redirections from my old domain, and use a canonical tag to the new domain. Do you think it' a good idea?

I would NOT do this - it may confuse Google more. Also, canonical is a "hint" which may or may not be followed whilst redirect is a directive.

Just a quick update. After almost 3 months since the domain change, the traffic is about 60% and very slowly recuperating, the ads CTR is high, but CPC is actually going down. I did increase the ads from 2 to 3 per page and that may explain the low CPC. Once the traffic reach about 80%, I'm planning to go back to 2 ads per page.

When you are transitioning between domain names it helps if you don't make template or layout changes at the same time.