Bundles can be great. Of the few I've purchased from Humble Bundle there has been at least one surprise game in each. I'd buy the package for one or two of the games, and then end up spending more time with the hidden gem.
I would have never purchased or played games like Offspring Fling, Snapshot, and Closure if not for bundles.
However, I am starting to see some repetition on just Humble Bundle alone, and I haven't seen what the other sites have to offer. And I get the feeling they're becoming too frequent.
Its training us as gamers to pay a few bucks and get a pile of games.. not exactly the best of ideas.