One thing that's been driving myself and our members nuts is the inability to upload an image directly into a post (apart from the attach method, which nobody likes and which only generates a thumbnail).
I know that's IPB related, rather than Gallery, but why not have a feature that lets you select a file from your local file system, uploads it directory into the posters gallery and also adds it the post?
I've tried explaining that they can upload to the gallery, then go create a post and add it, but most of them rightly give up, saying (quite reasonably) that they should be able to upload directly, just like you can almost everywhere else on the Internet... And I'd have to agree with them that, if it needs explaining, there's something wrong.
I'm getting a weird issue with Social Groups on my site ( http://www.flightsimulatornetwork.com/groups/ ).
More often than not, a click on any of the links doesn't do anything at all. You seem to need to click almost precisely in the middle of the link! I'm running 2.0.0 Beta 3, but this has happened in earlier releases, too.
Hovering over the link shows the tooltip for the link itself, so it's definitely a "live" link.