...a few years ago PA6T was best, next year Freescale T series will be the king of PPC
The P5040/5021 isn't that bad right now. When the T5040 (with AltiVec) is introduced (hopefully in the 23.2 to 2.5 GHz range) it should be pretty nice.
But none of them have as many PCIe lanes as the PA6T.
And who knows what A-eon and Varisys are up to. Trevor mentioned that they were working on more then one project several months ago.
The X1000, while expensive, actually is a pretty nice system. Sure, its slower then a lot of X86s, but compared to other PPC and ARM ystems its quiite fast with a nice complement of expansion slots.