I switched to HTTPS in Sept 2014 and my earnings are still down about 10%

...only HTTPS landing pages can be linked to from Adsense ads on HTTPS sites.

Has anything changed or advanced here?

Apparently people are still buying into this myth, so I guess not much has changed in that regard. The pool of ads is slightly smaller because not all third-party advertising networks support serving ads over HTTPS yet. Landing pages have nothing to do with this.

I suspect the whole idea has died a natural death.

Thanks for the clarification robzilla.

Google seems to force things on us that for whatever reason they find important.
An example would be mobilegeddon. (They wanted a more mobile web. They pushed us in that direction by promising better rankings, which yes I know didn't really materialize.)

The HTTPS thing is the same type of thing.
John Mueller Retweeted>> Gary Illyes ‏@methode Aug 18
If you're an SEO and you're recommending against going HTTPS, you're wrong and you should feel bad.

You would think that of all of the parties involved, the 3rd party advertisers who display through Adsense would be the easiest to bully into complying with HTTPS requirements, since there is a financial relationship there.

As it stands now, Google is basically pushing HTTPS but not complying themselves, nor making it an easy decision for us to comply too.

They wanted a more mobile web. They pushed us in that direction by promising better rankings, which yes I know didn't really materialize.

Users want a mobile-friendly web when they use mobile devices, and so mobile SERPs are now tailored to mobile users (i.e. it has certainly "materialized"). Google wants to keep its users happy, so if your site is not mobile-friendly, it may not rank as well mobile results (depends on other factors, too, of course).

As for HTTPs, it's the future for the web, and there aren't many valid reasons to recommend against it -- that tweet from Gary Illyes just does a poor job of explaining it. However, moving to HTTPS may require a significant investment of time or money for some companies, so these advertising networks may simply be stalling (or working on it). As more and more publishers move to HTTPS, however, their reach will continue to decline, and they'll probably make the switch eventually.

I never noticed a difference in revenue after switching to HTTPS, but apparently others' mileage varies.

I'm intending to switch my primary dozen sites to https by next summer.

Is there a reason for a blog that holds no user data whatsoever to switch to HTTPS just for ranking purposes?

I'm essentially the exact same situation as you LuckyD. I agree that the ranking advantage now is evidently minimal at best. But over the long term, I don't doubt that https will play an ever increasing role (to what benefit I'm not entirely sure, other than that's Google's wishes). But I don't necessarily think that the change in https importance will be directly related a specific update. Instead I would think it might be a factor that's constantly dialed up, to the point where if I'm not https I become increasingly more irrevelent in the SERPs.

I'm not planning a change soon. It's just that I assume I will be making this change at some point.

I would love to hear from other Adsense publishers who did make the change that did or did not experience a drop in earnings.

Could someone please refresh my memory on the actual, real benefits for both the publisher and the visitor for a https site over a http site?

Here I am speaking about a plain vanilla HTML content site, without any lah-de-dah gizmos, just lots and lots of boring words rendered by a .css file [all black readable text on a white background] accompanied by some explanatory .gif and .jpg files. Just boring stuff for geeky people. No visitor interaction.

Now I just did a HTTP vs HTTPS Test with the result?

The HTTPS was 126% slower than HTTP

Apart from Mr. Google's fascination [obsession], what are the real benefits for everyone by switching over?

Once upon a time we simply wrote words on the internet, then people came along to our sites to read those words to hopefully learn - now it has become so unnecessarily complicated - well though mine hasn't.

You'll probably see better results with SPDY or, preferably, HTTP/2 enabled, but HTTP/1 may still be faster for a simple site. Anyway, if HTTPS doesn't make sense for a site, there's absolutely no need to make the switch. You're not going to get a rankings boost just because your site uses HTTPS, except maybe in a rare edge case scenario.