Combining polls it conducted in August and September, Pew found that of people under age 30 with only cell phones, 62 percent were Democrats and 28 percent Republicans. Among landline users the same age that gap was narrower: 54 percent Democrats, 36 percent GOP.
Similarly, young cell users preferred Democratic presidential candidate Barack Obama over Republican nominee John McCain by 35 percentage points. For young landline users, it was a smaller 13-point Obama edge.
I'll be interested to really see what happens in November, because I expect this to have a significant effect. I've argued this with people who claim to be "more in the know," but I think they are full of it.
There IS NO conclusive evidence on how this new phenomenon affects polling. Period.