Photoshop CS2 works 100% on a Windows XP guest. The only problems you might have running professional imaging and press applications assuming you are using a Windows guest (although the same problems are probably true on OS X as well -I've got no experience of OS X so I can't say) are :
1) Hardware calibrating the monitor but that's essentially a hardware issue - although some programs will actually call the monitor and graphics hardware adapters directly for calibration - these will certainly fail. Professional imaging requires properly calibrated monitors.
2) Not getting enough resolution because the Parallels video adapter is still under development (Windowing etc).
3) High resolution special purpose professional printers such as FUJI Lightjets which have things like embedded RIP software embedded in them -- cost of these are however far beyond "typical users" and are only used in high quality professional labs. Professional scanning equipment is also likely (although not always) to fail as well.
Camera Tethered shooting is also another application which probably won't work on typical Virtual Machines as here again the hardware drivers will make actual hardware calls.
You won't need 3D for most Image type applications.
Warning however running Photoshop on a Guest Windows OS might need you to re-activate photoshop CS2 depending on how CS2 "sees" the hardware on the guest OS machine.
Adobe are quite strict with their whole licensing procedures - you can run CS2 on 2 computers normally a laptop and a desktop however you CAN transfer licenses back and forth between individual machines if you are testing.
Unless your programs actually make direct hardware calls rather than use Windows API's etc then everything should work just like it does on the native OS.
Cheers
-K
Last edited: May 18, 2006