I largely concur with your mockup.

Yes, they should have used the keyboard exclusively for the type keys, thus making every key a little wider. That is, I would keep the return key and backspace keys on the slider. [edit 'flag' buttons] Looked at hi res images - it's the menu button ... so you have three menu buttons?

I personally think the camera should have been on top in the middle.

And, since the camera no longer swivels ... how about a two megapixel camera on the back to take pictures? I had started to look at the N800 as a little mobile blog machine, but the N800 images are many times of unacceptable quality and when saved with the camera app take 250KB of space??