As a video editor, I hear a lot about the Mac Pro with duel Intel Xeon CPUs. Right now I edit with a PC with an i7 CPU and it works very well. Is there any reason for me to consider changing to a Mac Pro with Intel Xeon CPUs? These are very expensive computer and I wouldn't want to make a move if there wasn't a BIG improvement. Plus I have never seen a comparison between the i7 and the Intel Xeon CPUs. That would be interesting to see.
If they are using the same microarchitecture the only real differences between an Intel® Xeon® and an Intel Core® i7 would be that the Intel Xeon supports for ECC memory and some have the ability to work in a dual or multi-processor configuration. Some software like Adobe CS5 will take advantage of a number of extra threads. So with your Intel Core i7 you have support for 8 threads and the Intel Xeon runs in a dual processor configuration you can get 16 or more threads. The biggest reason why Mac had a reputation for graphics work really comes back to the support for Postscript that Macs have had for so long. Here is a comparison between the Intel Core i7-2600 and Intel Xeon E3-1275 http://ark.intel.com/compare/52277,52213.
I don't know which i7 you have but each has an equivalent xeon which performs the same. Even if you had an older i7, you wouldn't have much of a difference in performance vs a newer one. If you did want to upgrade, building you own pc would still cost a whole lot less than a mac with the same specs.