It's official: bubble popping games are now their own genre. We're not sure at what point a series of clones make the transition from 'ripoff' to 'genre,' but it's happened. This isn't to say that Bubble Witch Saga has nothing new to offer. The game has shades of RPG...things like items and independent levels distinguish the app from it's single-stage predecessors.
The social angle also makes for a fun twist. Your friends' ranks are constantly paraded before your eyes so you know exactly who to trash talk, who to compliment, and who to target for your next conquest.