Stumbled upon this via anime!anime!: a new manga called Wonder Comic, which is being serialized online. Nothing new there, but this one is being serialized via Twitter.
Basically the way it works is that each panel is posted to Twitter via TwitPic, and any dialogue, narration, or thought bubble text is posted with it.
That said, I'm not sure how easy it would be to get into something browsed that way. If TwitPic had some kind of "next photo" or slideshow option, on the other hand, it would seem a lot more feasible to me.
Now, this manga is in Japanese, of course, but if it was in English would you guys be checking it out?
(Twitter-tan (c) cola82.)