PC World just posted a review of the new Microsoft Natural Ergonomic Keyboard 4000. It's fairly brief, but the reviewer ultimately liked the keyboard: "As a touch typist, I initially found positioning my hands comfortably on this shipping unit difficult. But after about a day, I got accustomed to the way it felt. The well-padded palm rest made everything feel even more comfy."
Considering the price is around $65 (as compared to my Kinesis Contoured at nearly $300), it's probably worth checking out, though with all ergonomic toys, I recommend finding a place where you can try before you buy.
Here's a link to the original review: Natural Ergonomic Keyboard 4000