It's a hybrid device. The fact that it may be compromised as a tablet and as a laptop does not mean that it's not a great device. It's a new device category. In many ways, laptops can be considered as compromised desktops but that does not mean that they are not worthy devices to have.
The question is: what does it do better?
Is it a better tablet? No.
Is it a better laptop? No.
Laptops are better at being portable, so they are better than Desktops in this fashion. Is the sales pitch for Surface is that you don't have to carry an iPad mini along with your MacBook Air? Is carrying less things the sales pitch? Is that worth it for the compromise?
Netbooks did nothing better other than building the Cellular data connection into a cheap laptop. Because of this they had no repeat buyers. I don't think the Surface has enough "better" to overcome its compromise. If it could be easily used in its lap, then it would be "better" at something -- but it seems to me the Microsoft OEM's have spent more time thinking about that extremely common use case than Microsoft has.