Well they are all being released now.

AnandTech says:

"I still believe Microsoft has the right idea here. It just needs some more iterations."

http://www.anandtech.com/show/6695/microsoft-surface-pro-review

Performance good, screen excellent, price too high (because of the keyboard cover price).

But the biggest issue is the battery life - 4-to-4.5h - which is to be expected with the current i5 I guess.

If I were in the market (which I'm not) I'd probably be waiting for a Haswell refresh, and hopefully for the keyboard cover to become an included item, for that price.