Personally, I've always liked the idea of a larger tablet. Yeah, it's not as portable and it's definitely heavier. However, I would take a 13inch over a 10inch any day. The screen real estate increase is well worth it to me, as well as having a larger on-screen keyboard. It's not so much larger than a 10inch to the point of being unportable. I mean, I cart around a 14inch laptop all over the place. Now, releasing it for $650 is mildly retarded, especially with Android. Then again, they're going for a niche market who might be willing to pay that price.
Put windows 8, an i3, and an SSD in there and I'll consider it for $650. 1600x900 is a perfectly decent resolution on a 13inch screen, though I wouldn't mind a bump up to 1080p either.