Photoshop CS2 is being released in a few weeks. It can handle the raw mode properly from digital SLRs, including 32 bit color handling. This is a godsend, as the limitations of .jpeg are quite obvious for the 10% of pictures I take that have areas of low contrast in them. This would also be helpful for astrophotography and the product also has some tools for removing .jpeg artifacts. The thing is darned expensive, however. For the 32 bit handling though, I think I might get a copy.
It works on Macs & PCs, as you know and has some tweaks for the Athlon 64, but nothing particularly important to me at this time.