I like campaigns, though I understand how that can be up to the individual gaming companies. I mean, naturally I do not like Dark Avatar's campaign. It had the makings of being really good, and just a little more polish would have made it really good. Stardock needed somebody with a heart for the campaign.
Starcraft II's campaign was one of the best I've ever played. Utter Darkness is my favorite battle within it.
I tend to like campaigns in general, particularly as a form of tutorial. One problem is that campaigns which also serve as a tutorial do not tend to have good replay value. The nonlinear campaigns like Rise of Nations:TnP, Rise of Legends, and Warlords:Battlecry 2 are among my favorites, but they have no tutorial value. In fact, the first battles are the hardest. CnC's campaign was really good, but the Scrin was bugged.