I feel your pain my out there, my brother or sister Mac user!
I, too am considering a G5 tower (my G3 B&W 400MHz is just slow, but knock on wood has not had a major glitch since I put in a new power module 2 years ago). Thanks for a great ride on this one Apple but if I can hold out suspect that before WWDC (read May) we will see Tiger on the street.
It just irks me to fork over another $200 (less than what my old B&W is worth today!) to update to Tiger. This would be the case if I gave Apple $3K for a new desktop and display now (three months before Tiger).
So, guess what? I'm waiting just like the rest of you. Will lagging sales motivate Apple? It'd better! I don't see Apple raising the street product of the hardware that's been out since 2004 to compensate early PPC adopters, do you? Have they ever?