Its not CS3 for free, and it is a beta, not a full working version. I believe Adobe have purposely made glitches in the software so it cant be used commercially, or for any serious work.
The brush cursor does not show making it annoying and difficult to use properly, and the image resizing function is also has its faults, making images jaggered and rough after resizing. These 2 issues alone make the software unusable for my applications.
But it is only a beta, and there are some nice new features, so I say the sooner they release CS3 the better.