Former presidential candidate John McCain took some heat on the presidential campaign trail after admitting he was still “learning how to get online,” and was then lampooned after an aide claimed the BlackBerry is “the miracle John McCain helped create." But the Arizona senator, 72, is one of the Tweeple. Today he will participate in an interview via Twitter, the microblogging site favored of late by journos, politicos and other constant communicators.

McCain is set to dish with ABC News’ chief Washington correspondent George Stephanopoulos at noon in what the host of This Week is calling a “Twitterview” (and what his colleague Ned Potter suggests might better be dubbed a “Twinterview”). “We're going to attempt to conduct a full interview exclusively on Twitter—complete with the 140-character limit!” Stephanopoulos wrote.

We learned during the presidential campaign that the BlackBerry was the “miracle that John McCain helped create,” according to an aide to the failed GOP candidate. And what a miracle it’s turned out to be for an enterprising reporter who poked around at a garage sale the campaign held in Arlington, Virginia, last week, turning up two BlackBerries with more than 300 contacts still loaded on them.

Tisha Thompson, an investigative journalist at WDCA-TV, the Washington, D.C., Fox News affiliate, reports that she paid $20 a pop for the devices, which contained phone numbers of McCain donors and supporters as well as e-mails, calendars and photos. 

Could next election season's dirty tricks include disclosures about the candidates' genes?

This year we heard all about John McCain's battles with skin cancer and Barack Obama's smoking habit, but there were gaps in their health records. It was unclear whether McCain — at 72 he would have been the oldest president elected to a first term — had been screened for memory deficits, or whether Obama had stopped smoking. Now, the proliferation of genome profiling products suggests that candidates' DNA could be fair game for public consumption, according to a commentary in today's New England Journal of Medicine.

Voters know a little bit more about Republican vice presidential nominee Sarah Palin’s health as they head to the polls today. According to a two-page letter released by her physician last night, Palin, 44, is in "excellent health and has no known health problems that would interfere with her ability to carry out the duties and obligations of vice president of the United States." 

Until now, Americans knew next to nothing about Palin’s health, other than that she gave birth to five children, the youngest of whom was born with Down Syndrome in April. (People with Down Syndrome have an extra copy of chromosome 21, and have mental and sometimes physical deficits, including heart abnormalities.) According to Palin's doctor, Cathy Baldwin-Johnson, the births were the only time the veep wannabe has been hospitalized.

Last night's debate between vice presidential candidates Joe Biden and Sarah Palin showcased their differences on energy policy and climate change, and also reminded us of some intra-ticket differences on those key scientific issues.

Palin, the Republican governor of Alaska, reiterated that she does not believe that global warming was solely caused by humans, a softer stance than that of running mate John McCain as well as that of the International Panel on Climate Change, which determined that it is "very likely" man-made. As Palin told Katie Couric on the CBS Evening News earlier in the week, climate change is a problem, but people are not the only culprits.

"I'm not one to attribute every man — activity of man -- to the changes in the climate. There is something to be said also for man's activities, but also for the cyclical temperature changes on our planet," she said last night. "But there are real changes going on in our climate. And I don't want to argue about the causes. What I want to argue about is, how are we going to get there to positively affect the impacts?"

Public fascination with Republican vice presidential nominee, Sarah Palin, extends to her views on the environment, evolution and abortion, and that curiosity has only grown since media access to her has tightened in the month since Sen. John McCain picked the Alaska governor as his running mate.

We have a bit more clarity now, after CBS Evening News anchor, Katie Couric, grilled Palin on last night's broadcast. Although Couric wasn't able to nail down Palin's positions as concretely as she (and voters) may have liked, she brought out some of the candidate's reasoning on controversial science topics.

Presumptive Republican presidential nominee John McCain today surprised the nation by picking first-term Alaska Gov. Sarah Palin to be his running mate. At 44, Palin is three years younger than Democratic presidential nominee Barack Obama; she is the mother of five, including a son who is in the Army and a baby born in April with Down syndrome.

By choosing Palin, McCain is clearly hoping to appeal to Hillary Clinton supporters, including women who have been slow to warm to Obama. But it's a big question mark whether they will cotton to Palin's conservative leanings: She is antiabortion and an advocate of drilling offshore as well as in the pristine Arctic National Wildlife Refuge (ANWR).