It's possible. In a conversation with us, game executive producer Tim Ramage said that both platforms are "viable platforms" for the game.
“At the moment we are only announced for XBLA and DS but we are looking at all other platforms for possible opportunities," Ramage said via e-mail. "Both the iPad and iPhone would be viable platforms for Puzzle Quest 2 to be a part of.”
The original Puzzle Quest (Chapters 1 and 2) [App Store] launched on the App Store in December 2008 following the full game's Xbox LIVE Arcade release in October.
The iPhone port was met with middling reviews until perfomance updates brought it up to speed with its platform counterparts, but it's always maintained that magical mixture of Bejeweled-style match-three play with RPG trimmings. Definitely check it out if you're a puzzle game fan.