Interesting, thanks for heads up Mik.
After reading about it for a bit, from what I understand the support is there, but it is only capable of registering a new type as being searchable or not. In addition, you can only do that in plugins (or in a functions.php file in your theme, I suppose).
It seems they have it on the agenda, then, but we are a ways from officially-supported fully functional custom content types then, with unique custom field sets and write panels.
Here’s to hoping for 3.0!