P4 will be around and is worth supporting in my opinion. We are months away from a Mac version, any many are waiting for the bugs to be worked out. I see people are setting up in P4 then importing into P5. Due to the hardware demands, that solution may be around for time to come. Also, P4 things can be used in P5, but not the other way around. I think P4 textures, props and objs will just have a broader base. Keep them coming!