The multiplayer (beta, but it works flawlessly for me) patch can be found on MacPlay's website in the downloads section. <a href="http://www.macplay.com/download
,</a> I believe.
This patch seems to have addressed some performance issues as well. I used to get 20-30 fps on my G4/500 MP (512 MB RAM, 10.1.2, Radeon), but I now get in the 40s at most times. I play at 1280 x 1024.
The game looks *stunning*. The landscapes go on seemingly forever, and the gameplay, while not entirely unique, combines the elements of different genres so effortlessly that you simply have to see it to understand.
Also, the OmniGroup (who did the work on the port), actually was able to ADD multiprocessor support to the game. On their website they state that they get the same framerate on their G4/500 MP (like me!) as on their 1.3 GHz AMD Athlon w/ GF3. I really love the work the OmniGroup has done on all of their products, but perhaps Giants most of all.
As for single processor machines, I get acceptable framerates on my Ti PB 667 (Radeon Mobility, 512 MB RAM, 10.1.2), but only at 800 x 600. I haven't run the latest patch on this machine though, so it may have improved as well.
There were some major bugs in the original game, but those have all been resolved in the patches. The game has gone through a second duplication run, though, and shipped with the latest bug-fix patch already applied. All that is needed is to add the multiplayer (I think it was a 4 MB download). I would strongly recommend DSL/Cable or a higher connection to play the multiplayer. Otherwise ping gets too high and everything becomes jumpy.