I think Reddit is just a symptom. I don't think it's going to be a Google killer but the fact that people are looking to it to fix Google's problems is a sign of the problem at hand. They are abandoning something bad for something slightly less bad at solving the problem at hand, or just desperate for any method. And Reddit is definitely unintentionally doing this. The only reason Reddit isn't gamed (or maybe it is?) is because it's a new phenomenon so far.