Looks like Andy Ihnatko was at least partly right: Panelfly will be available on the iPad. It seems unlikely that it will be included out of the box as he speculated, although their wording and the reticence of the company’s CTO to speak on their purchase model leaves some wiggle room for an Apple announcement.
(Sorry about the TUAW link; the original article no longer exists.)
UPDATE: Andy Ihnatko still likes Panelfly, but appears somewhat dubious regarding their chances without some more serious support from the comic publishers.
