One big thing you guys are forgetting is that if there is no LAN play for skirmishes, if battle.net goes down you are screwed and stuck with single-player only.
And when I say battle.net goes down, I mean goes offline forever. Don't think it is a real concern, then you have no valid real-world vision of how corporations work. They can and do drop all the time, get bought, sold, etc... And when that happens, what happens if SC2 isn't considered "profitable" enough to keep the servers online for it?
On top of that, I just realized, are they going to be charging monthly to play on battle.net servers? Or are they free-play servers?
If they charge for the online servers monthly, I will be returning at least one if not both copies I have sitting on my desk. To not allow LAN play for free for skirmishes is one of the big reasons I bought this to play with my 12yo son. I will have to look into it further.