Joystiq has a Puzzle Quest 2 preview online after playing a preview version of the game with Infinite Interactive's Lead Designer Steve Fawkner. Here's a quick taste:

JS: Puzzle Quest 2 seems like exactly the kind of update fans will want: a few new mechanics and a new setting built around the same core gameplay. The team is very aware of fan feedback on Galactrix, and even though Puzzle Quest 2 is a very different game from Challenge of the Warlords, I'm definitely looking forward to sinking some hours into the RPG/gem-matching mashup when it comes out later this summer.

Check out the full preview on joystiq.com.