No, they don't allocate the commission until shipping (neither do they charge the customer until then, so it's fair enough).

If it's something that's going to be "hot" in your niche, it does pay to have a link so people can pre-order through your site. If someone finds a better deal before release, they might delete the item from their cart, but my experience is that most people leave it there. So you don't get paid right away, but you do get paid. And you're ahead of the sites that don't post the pre-order links.

As a side benefit, if you're in a niche that has "hot" releases fairly often (like one of my sites is), customers will come to trust you to have products available right away and may come straight to your site instead of hunting around. The day the most recent niche DVD release was announced, I got a couple of emails asking me where the link was! (You can bet I got a notice up immediately, saying it wasn't available even for pre-order yet, but the link would be there when it was.)

As noted, Amazon pays commissions ONLY when an item is shipped (and they deduct the commission for returned items).

I think the applicable commission rate will depend on Amazon's terms at the time the order is shipped, so if someone pre-orders Windows Vista, and it ships in Q1 2007, then your affiliate earnings will be based on your site's commission rate for software shipments in Q1 2007, not on your current-quarter commission rate or tier. Usually, this has very little impact on net earnings, but if your traffic is highly seasonal, this can be a significant difference (and of course, if Amazon makes changes to its program, the difference might also be significant).

Quite frankly, I don't think it really matters -- if you think your customers are interested in pre-ordering a product, then promote it and let them pre-order it at Amazon. You'll eventually get paid something for the activity. However, if you are spending money to drive traffic for these pre-orders, you should be very conservative in your estimate of the earnings, since (a) the commission percentage might change, and (b) some of the orders will probably be cancelled or declined before shipment, and there might be a higher-than-average rate of returns. (A common problem with pre-orders is that folks use a credit card which expires during the interim, and thus can't be used when the shipping date arrives. Also, some folks who pre-order forget they did so and buy the item at retail when it is released, then refuse or return the pre-order shipment.)

Thanks everyone!

The good thing is that I know the item's price and release date :)

Markwelch makes a good point about driving traffic. That's not something I concentrate on for that site, mostly because it's in a very closely-defined niche and the biggest issue for sales is having people order through my site instead of someone else's, so getting links up fast is very important. If you need to pull in customers from a more general audience, you're going to have different considerations.

The good thing is that I know the item's price and release date

Not necessarily... With the DVD release that I talked about in my earlier post, Amazon added pre-order links even before the distributor's "official" pre-order date - to say nothing of the release date; the initial pre-order link didn't even have a cover image yet. Amazon also seems to have changed its shipping policy. Used to be that they wouldn't ship a pre-ordered item until its official release date, so if someone wanted, say, a DVD on the first day it was available, they'd buy it locally rather than wait a couple of days for it to come from Amazon. Lately, though, my customers are reporting receiving items on the release date, which is good news.

Amazon's price was/is also about 30% lower on this DVD than the suggested retail price. Since people had been complaining about what the DVD was going to cost, this was very good news.

So, if you think it's going to be an important release for your site visitors, keep your eyes open and take whatever selling advantages Amazon gives you over other purchasing options.

Something to watch for: occasionally Amazon may use a pre-order ASIN and then at some point replace it with another. You'll need to update your links.

How often this happens I don't know, but I remember a very angry Amazon Associate on the Amazon discussion boards who had gone after an upcoming Harry Potter book, only to have their links stop working when Amazon changed to the real ISBN shortly before the release date.....