It's pretty good. You can make a 2D, and 3D game with it. ToonTown is coded in Python, so you can make an mmo with it, if you have that knowledge.
Some good tutorials are here:
http://www.youtube.com/view_play_lis...1FEF17E1E5C0DA (43 Videos?)
And,
http://www.youtube.com/watch?v=0xgn-...e=channel_page (19 videos, not completed yet.)