Merging Live and Skype Accounts is a problem for me personally since I want to use Skype on insecure WiFi (and obviously my Live account is also an e-mail account).
Microsoft trying to shove the tablet experience on the desktop is going to hurt them big time. Now they kill MSN messenger, all latin america will be very sad, they still use that software down there.
It docks the windows 8 app to side. You can chat away with skype by doing so.
I don't have a Surface (yet) but I bet that feature alone makes it worth it for multi-taskers.
a) swiping from the top edge to the left or right (current app)
b) drag an app out of the switcher to an edge
[These also technically work with a mouse; but far more convenient with touch]