I am looking at getting a new workstation for editing, post-production, and 3D work. Would it be better to have a system with two quad core xeon processors (2 GHz each) or one faster quad core xeon processor (3 GHz)? Thanks.

Persoanlly I think one cpu should generate less heat and works better.

we'd need to know, when you say you'll be doing "editing, post-production, and 3D work..." do you mean all at the same time, or one at a time? a faster single core is better if you want the best performance in a single application, and you only run 1 application at a time. dual core would only produce performance benefits if you want to be running two or more applications at the same time (or software written to utilize both cores, but not much does this yet).

That may be my answer. I typically have more than one program open at once. I work a lot with a number of Adobe products and it is not uncommon to have Premiere, After Effects, Encore, and perhaps a graphics program like Photoshop or Fireworks, all open at the same time. And often, I will have one program rendering something while I work in another.