Re: [math-fun] Computer Algebra Systems

And my first question is: are there any general CAS discussion groups around any more out there?

sci.math.symbolic

Second question: would Maple version 12 on a current Mac be any improvement in these and other respects?

I don't have a personal experience, but AFAICT yes. It is not perfect, the classic interface is missing, but some Java issues were fixed. There is a new update, Maple 12.01 which fixes a few more issues.

Third question: have Apple yet managed to install a C compiler which actually compiles GMP?

Yes, SAGE (available from http://www.sagemath.org/ ) includes GMP, and it works well on Mac - William Stein has Mac on his laptops. Alec Mihailovs