QUOTE(Destroyer E @ Jul 27 2006, 04:09 PM)

Having done some ingame recordings myself (not WoW though), I do notice a performance drop in the game. However, you're on a G5 with 1.5 GB RAM, while I only have a G4 with 1 GB RAM.
I think it's possible to get something decent. Just don't do the CPU intensive recording.
I just downloaded Snapz Pro and tried it out. At full screen on 1024x768 I was able to get 10 fps recordings while playing at 10 fps on my 1.5 GHz 15" G4 laptop, 1GB ram, upgraded vid card. I never get great framerates anyways.
A couple of notes:
You've got to start the recording in windowed mode since WoW takes over the screen, but you can go into full-screen.
Reducing graphics settings is a good idea. I'm going to try bringing my res down to 800x600.