Well, I actually had a lot of trouble with the 2.0 version. It "collapsed" (I'm not sure if a program can "collapse" but I'm too lazy to look it up xD) all the time and I really had to save every single step I did; anyways, I've read that I was not the only one with that program, that makes me somehow happy xD Nevertheless, it's a great program for all those who can't (or just don't want to) spend money for a program like Open Canvas or Paint Shop Pro (although they're actually very cheap compared to Photoshop), in my opinion it has everything you need to draw and to create nice graphics. The acutal 2.4 version seems to run quite stable and now it's possible to use Photoshop brushes directly in GIMP. You are even able to use downloadable Photoshop filters, you simply need to download a certain file which I forgot how it's called... I will check this out later.
The only "bad" things are that using quite big brushes in their original size can be a pain in the neck and it doesn't seem to be able to flip or rotate your brushes, which would be extremely helpful if you use for example grass or leave brushes.