Obviously IANAL, but my reading of eula.txt included with VS9 seems less
restrictive than the 2003 one.  It has 2 clauses that seem relevant:

* [you must] require distributors and external end users to agree to
terms that protect it at least as much as this agreement;

* [you must not] modify or distribute the source code of any
Distributable Code so that any part of it becomes subject to an Excluded
License.  An Excluded License is [description of GPL]

I do see how the first could be considered an issue (otoh, I'd try to
argue we aren't doing anything to imply any worse terms :), but I don't
see how the second is, even for GPLd programs that simply used the compiler.

Maybe it would be helpful if you referenced the specific clauses you
think are of concern?