I've been an application developer for AIX and Power7 for almost 2 years, and I'd say the grind rate is pretty impressive. Developing for power is a bit of a bitch, and the hardware is expensive but it is certainly an impressive slice of engineering.

I'm curious if anyone knows why chips like these are being used today.

If you already have software that parallelizes to 16 cores, why not just use a few more x86 cores and save a lot of money?

Wow, 16 cores on one die. 128 threads. I can't wait until this makes it into consumer-level hardware. (I'm not sure what I'll do with it, but "build it and they will come".)