LN2 is used by people who are pushing their CPUs past all reasonable limits. And it has been around for a while, so it isn't really anything new. And I don't think they will quite get to the performance you can squeeze out of a chip on LN2 without doing bad things like melting your aluminum case when it reaches around 600c. Heck, you could boil your aluminum case at the temps those chips could withstand. Needless to say, you shouldn't be seeing this in use on consumer computers when a fault condition could melt your heatsink into a puddle of molten metal.

I have a hunch this will find more use in things like electric motors where heat really is a limiting factor in performance. Or in aerospace (like they are used currently) where the chips need to resist radiation and extreme temps. Also, uses in power-distribution seem possible. Imagine handling twice the electrical load on the same size. Of course, this might increase the risks of Transformers Exploding/Arcing... ( http://205.243.100.155/frames/longarc.htm - these videos are must see )

Anyways, we just have to wait and see who decides to use this.