For those of you considering to purchase this one to replace desktops, this one is still pretty slow relatively. If you are running Core 2 Quads or Phenom II X4 OCd, you won't get much performance increase, because notebook IVB i5s are still dual cores with hyperthreading, and U models are low clocked. Even against old dual core Desktops, this one isn't that much better. So get this only if you value portability and weight the most.
For example: IVB i5 @ 1.7ghz even compared to OLD core 2 duo OCd @ 3.4ghz is:
3317U about 30~40% faster using 1~2 threads (with turboboost)
About equal in performance using 4 threads or more.