As someone who has been following the election closely (though from the outside), I think Americans have the choice between two fundamentally different views of politics.
In Obama, you have the intellectually curious genius. (I think it's fair to call him that: B.A. in international relations from Columbia, Magna Cum Laude Juris Doctor from Harvard, professor of constitutional law at Chicago) He has been emphasizing policy and ran an almost exclusively positive campaign until recently.
On the other hand you have McCain. Academic underachiever (894th out of a class of 899), troublemaker, known as a hothead. He has played an emotional campaign based around his time as a prisoner of war. His ads have largely been negative. I think his campaign manager outlined their strategy best:
http://voices.washingtonpost.com/thefix/2008/09/mccain_manager_this_election_i.htmlRick Davis, campaign manager for John McCain's presidential bid, insisted that the presidential race will be decided more over personalities than issues during an interview with Post editors this morning.
"This election is not about issues," said Davis. "This election is about a composite view of what people take away from these candidates."
They bet everything on this, because policy wise they fail flat out.
Consider the comparison of the tax proposals:

(The original data comes from the washington post)
So when McCain says "Obama wants to raise your taxes" - it's technically true, assuming you earn over $600,000. (he never says Obama raises taxes on everyone) They're good at the semantics game. Governor Palin is using the line about ebaying the jet in her stump speeches. McCain used it as well and said "she sold the jet on ebay = and made a profit." Some research shows that she did put up the jet for auction, but it never sold on ebay. They hired an outside company to sell it later and they sold it below the purchasing price. Still, it's a profit compared to having the jet grounded. I don't think this is a fair way to campaign - it's clearly not what voters imagine when they hear the line.
McCain's health care proposal is quite bizarre. First of all, employer provided benefits would become fully taxable. There is no tax credit. If the employer stops offering you a health insurance plan and you buy it yourself, then you get a deduction. ($2,500 for an individual, $5,000 for a family) The problem is that employers contribute far more than that to health insurance. Either way, it is going to be a tax increase. (see graphic attached at the end)
I think the social issues can't really be debated as they're usually based on faith/belief and not rational arguments. However, I do find it concerning that Gov Palin attempted to fire a librarian for refusing to ban certain books. During her time as a mayor of a town of 6,000 people, she also managed to get $20m in earmarks from Washington and go from no debt to $27m debt during her term. To me, it's painfully obvious that she was picked to pander to the socially conservatives, not the fiscally conservatives. (I actually share many views with the latter.)
Polls right now have to be taken with a HUGE grain of salt. They usually poll likely voters, which means those who have voted in the past. The Obama campaign has spent a lot of money on registering new voters, who aren't included in the polls. It's also likely that african-american turnout will be higher than in the past, which isn't reflected in representative polls. (they take turnout from previous elections) There's also the issue that younger voters rely primarily on cell phones and many no longer have a landline. Polls are conducted over landlines, so they're also not included. In favor of McCain is that many Republicans may not respond to polls as they aren't excited or possibly even hesitant to identify themselves as Bush supporters. This may be gone now with Palin's nomination, which would explain why McCain's numbers are jumping. (only in some polls though, others have them where they were before the conventions) We also have to consider the so-called Bradley Effect. That is people may not want to appear racist and thus tell pollsters they will vote for the black candidate. In the privacy of the voting booth, they'd still cast their vote for the other candidate. Nobody knows if this still holds true today, or on a national level.
edit: Oh, I forgot to add this: McCain also claimed that Obama raising the capital gains tax would affect everyone in their retirement savings. This is flat out wrong, as 401(k)s are exempt from capital gains taxes. The same applies to traditional IRAs as well as Roth IRAs. This is where most Americans have all their retirement savings. (exactly because of the tax breaks...)