There are supposedly two keyboard types: a thin membrane one and a thicker one with more travel and clicky keys (probably more like an Apple keyboard at that point).
I keep saying this, but again: the Surface RT will not be competitive at the low end against the iPad and Kindle Fire. The Surface Pro will not be competitive at the high end against the ultrabooks and Air.
It's a weird machine, and I think the ultrabooks are better for people who want Windows or Linux on a thin/small form factor.
Here's another thought: the Surface probably won't balance well on a lap, like an ultrabook can.