HT might actually work this time.
Actually while HT on the P4 (at least earlier ones) wasn't exactly impressive, SMT (symetrical multi threading, which is what HT is) has been quite successful on properly designed CPUs, like the powerpc and was looking very promising on the Alpha 21464 (which was never produced but is where intel got the idea from after they took over the Alpha technology). Sun seems to have quite goot performance on their multithread capable CPUs.
The main reason HT doesn't work well on the P4 is that it doesn't really have many spare execution units most of the time, and even if it does the dispatcher seems to be too small so it can't actually start executing new instructions even if it has room to execute them. The tiny L1 cache probably doesn't help either if you have to start sharing it between two threads.
Perhaps intel ought to come up with a new name since they botched HT first time around.