10:18p.m.: Maybe it wasn't just expectations-setting when Obama's campaign said he hadn't had much time to prepare? He's looking at his notes a lot.
10:17p.m.: The debate is almost over, and Obama hasn't mentioned Bain or "47 percent."
10:02p.m.: "We've seen this model work really well. In Massachusetts," Obama says of Obamacare. He runs over time, and Lehrer tries to stop him. "I had five seconds left before you interrupted me," he says, a little snippily, and then tries to cover with a smile.
Obama wants to keep talking about Obamacare vs. Romneycare because he thinks its a strong point for him, and makes Romney look like a waffler. Romney says that Obama pushed through Obamacare without Republican votes. Obama responds that Democratic legislators in Massachusetts could have given the Republicans in Congress some tips on working across the aisle.
10:00p.m.: Guys, this is a bait and switch. We were promised a substance-free zing fest, in which "not looking smug" was the highest priority, and yet we've got a real lecture on real issues. The people will revolt.
9:49p.m.: We're halfway through the debates. No knockout zingers so far. Obama seems a little tired. But how are they doing on the all-important side-by-side shots? They both are doing a lot of insincere smiling.
Here's Obama saying Romney's plan to offer vouchers for Medicare would end up costing seniors more, because the size of the voucher would not rise at the rate of health care cost inflation.
Obama while Romney says they wouldn't pay additional money, they would just get more choice.
9:45p.m.: Twitter says there were 17,000 tweets per minute for "Big Bird," 10,000 tweets per minute for "PBS."
9:38p.m.: Romney denies Obama's assertion that companies can get a tax break for moving companies overseas. "I've been in business for 25 years. I don't know what you're talking about. Maybe I need a new accountant." Zinger!
9:34p.m.: Romney tries to personalize spending cuts. No more subsidies for public television. "I love Big Bird! Actually I like you too!" Lehrer is pleased.
The 80-year-old moderator is turning out to be a fun part of this debate.
9:30p.m.: Romney demands the last word on taxes. "He had the first word so I get the last word!"
Jim Lehrer seems to love this.
So does Obama.
9:20p.m.: They start fighting over a nonpartisan study that found that Romney's tax plan to lower rates and pay for it by eliminating some deductions was impossible unless he raised taxes on the middle class. Though Romney's prepared zinger got a lot of attention before the debate, Obama apparently practiced some, too. "His big, bold plan is 'nevermind," Obama says. Under Romney's plan, "Donald Trump is a small business. And I know Donald Trump doesn't like to think of himself as small anything, but that's why their plan says."