You kind of just answered it for yourself. So far the environment has been volatile from week to week. I also really wouldn't trust generic ballot polling since it really doesn't matter that much. Only state and congressional polling matter right now.
There seems to be a lot of contradictory information, and the generic ballot is very tight with each poll swinging it one way or the other.
Part of this is the politicization of polling. Several polling firms have their own agenda: generating a poll that has Gardner leading Udall by 3 for example, gives donors more reason to give money to Gardner. Most of the posters around here don't trust Vox Populi polls, for instance, because it's operated by Mary Cheney and it's been releasing polls that much more Republican than others are showing. Nobody really took their poll that showed Merkeley trailing seriously.