"Likely voter" models are flawed

Okay... so apparently the BIG BREAKING GOOD NEWS for John McCain is that he leads Obama 49% - 45% among "likely voters". Here is what is wrong with that lede:

1. It was conducted only on the weekend, which underestimates Sen. Obama's support, as his younger voters are less likely to be home.
2. Sen. Obama leads among registered voters 47% - 44%
3. "Likely voters" means whomever the pollster thinks is going to vote, but who knows in July who is going to vote?
4. As detailed here: "From registered voters to likely voters, they took 8 voters from McCain's total while taking 67 from Obama."
5. That means that despite the "enthusiam gap", the pollster decided that only 2% of McCain's supporters weren't going to vote, versus 16% of Obama's supporters

People, we can't afford to be cocky, but seriously, the article surrounding the poll says it best:

Gallup editor Frank Newport tells Jill that "registered voters are much more important at the moment," because Election Day is still 100 days away.