I kind of like this idea. What's going to stop enthusiasts from "unlocking" these features down the road for free? It will be like unlocking shaders on video cards or additional cores on AMD X2.
I can see 'keygens' further down the road tbh just like with software. Could be interesting if for arguments sake the i5 760 has HT hidden/disabled though and you just need the right code to unlock it. Could be fun times.