AMD64 CPU's support all of the above and also run 32-bit code.
The coolest things to me about the AMD64 CPU's are:
- Memory controller built-in to CPU.
- Full-speed front side bus (same speed as CPU).
- Totally ownz Intel chips 1GHz faster and with double the cache.
I'm sure in the next iterations of AMD's CPU's, they'll incorporate the SSE3 instructions and have a few more frills to edge out Intel... again.
HP/Compaq will soon begin selling AMD Athlon 64 (FX) and Opteron systems, so Intel's already lost the short-term battle.
Btw... a car costs less than an Itanium 2 system, so that's not a real bragging point. :p