Barring, of course, Megatokyo. In any case, the reason I stopped reading CAD was because it stopped being funny and it seemed as though Tim was trying desperately to make me care about the cast. After he had been selling Ethan as a digital punching bag for all stupidity and mishap (while being funny) I was irritated by the sudden change (mostly because of the lack of funny). Plus I don't like Tim Buckley. He was a complete jerk when I emailed a complaint to him.
I think the reason most webcomics don't appear to present story and continuity is simply because if you notice it, you aren't laughing.
Most of the webcomics I read have a story to it (Megatokyo, Real Life, MacHall) not to mention all of the paper comics that have made the transition to the web. Calvin and Hobbes has plenty of story. Even Penny Arcade has story once in a while. Gabe and Tycho know when to use it, however, so as to keep the funny coming.
It'll be interesting to see what people think of it. I'm certainly not going to pay for anything. I'm not a fan of CAD anymore. Even if I was I wouldn't pay for anything. Not unless I get a preview and it has me rolling on the floor.