i know this seems like a dumb question, but if I had the Mac version, would i still be able to interact with the creatures that were created on PC's or is it platform specific?

I have no idea, and I have never thought about it... It makes sense to me that you would be able to share creatures no matter if you were on a MAC or a PC (but I may be wrong.)

i'm about 98% sure that they're not platform specific; they're all just PNG files and the fact that both PC and Mac versions are on the disc, and presumably use those same Maxis-authored creatures implies that those files are platform independent.

also, if they were NOT, we would see different sections on the web-based sporepedia for each platform, but there's no such segregation.

Cool thanks

It most definatly isn't, been running it on my Macbook Pro and have been able to connect to PC users without a problem, same software, same servers, just configured for the different OS's.