I have only played a very small amount of the campaign, but it does look fun.
I also played a little bit of a SP GC Game as the rebs. Let me put it this way, I was attacked at Yavin by an Imperial fleet consisting of Thrawn, Piett, Moch (I didn't even know the Arch Hammer was in this game! w00t!), and another regular ISD. Yeah, my fleet of 8 frigates with some fighters got owned! I loved it!
Otherwise, I have played two online skirmishes. I think it's safe to say that the online skirmish games are tons better than what you get in regular EaW. The new ships are pretty cool and...oooo, B-Wings are UBER AWESOME!
Final comment is that I LOVE the replay feature. I've been wanting that since I bought regular EaW.
Put simply, Petro hit a home run with this expansion IMO. Good job guys!