Republican presidential candidate Sen. John McCain has a 6 percent chance of dying of the skin cancer melanoma in each of the next two years, says a doctor who specializes in the design of medical trials.

McCain, 72, has battled melanoma four times, most recently in 2002. After his campaign released 1,200 pages of his medical records in May, his doctor said he had less than a 10 percent chance of the melanoma recurring.

Now, in a letter to the medical journal The Lancet, internist John Alam explains his analysis of those records, based on a predictive model for 10-year survival in melanoma patients. Alam is a biotech consultant in Massachusetts who's contributed money to the Democratic Party and its presidential nominee, Barack Obama.

How much do voters need to know about a presidential candidate's health, and what information should politicians be obligated to share?

The New York Times takes an in-depth look at those questions today, concluding that candidates are sharing less medical information now than in some recent elections, despite candidates' previous health concerns. According to the article, the presidential and vice presidential candidates have only released limited and, in the case of GOP veep pick Sarah Palin, no medical records to date.

We know from a May review of some of John McCain's medical records and from previous reports that the Arizona senator has battled the most deadly form of skin cancer melanoma. His physician says McCain, who at 72 would be the oldest man ever sworn into a first term as president, has not  displayed any memory problems, but she has not said whether her patient has undergone cognitive tests.

Does Joe the Plumber play video games? We're not sure what hobbies the invisible star of last night's presidential debate indulges in, but as far as Democratic presidential nominee Barack Obama is concerned, if you want to register young, eligible voters, you need to go to online gaming sites.

The Illinois senator is touting his online voter registration and early balloting drives in ads on Microsoft's Xbox Live service, Reuters is reporting. For Obama, who is more popular among youth than his older Republican opponent, Arizona Sen. John McCain, the ads are an opportunity to reach 18- to 34-year-old male voters.

A 26-year moratorium on offshore drilling will expire on Wednesday, after the House approved a temporary-spending package today sans a planned extension of the ban. The bill was approved by a 370-to-58 margin, hours after the Democratic majority nixed a provision that would have maintained the prohibition on drilling off the U.S. coast line.

The measure is likely to be approved by the Senate within a few days, the Associated Press reports. President Bush had threatened to veto the package if it extended the ban.

Democrats backed away from their longstanding support of the drilling limit over the summer, after fuel prices skyrocketed and consumer discontent over the surging costs became a top issue on the presidential campaign trail. Both candidates support offshore drilling; Republican John McCain wants drilling allowed on the Outer Continental Shelf, while Barack Obama backs offshore drilling if it's accompanied by development of alternative energy sources.

Barack Obama's campaign has dissed his opponent John McCain for his supposed lack of computer competence. While some have come to McCain's defense, a new study indicates the Obama camp is making better use of technology than McCain's people are.

A recent study by Pew Research Center's Project for Excellence in Journalism finds that Obama was first to use the Web as a campaign tool; the think tank says McCain's crew has finally gotten on board, recently adding a social networking component and other new features. Too little too late? Looks that way, says Pew, noting that Obama’s online social network of registered users is more than five times larger than McCain’s, according the sites’ own accounting, and his site draws almost three times as many unique visitors each week.

First he told us he was the driving force behind Wi-Fi and cell phones. Now John McCain — who in July was still "learning how to get online" — has another tech feather in his cap: the BlackBerry.

The CrackBerry is "the miracle that John McCain helped create," an advisor to the GOP presidential nominee told reporters yesterday, adding to the snickering around McCain's statement earlier this week that "under my guiding hand, Congress developed a wireless spectrum policy that spurred the rapid rise of mobile phones and Wi-Fi technology."

With advisor Douglas Holtz-Eakin's words echoing through cyberspace, the Al Gore comparisons are coming fast and furiously now — though we'd like to pat ourselves on the back for noting the similarity on Monday to the former VP's infamous declaration: "I took the initiative in creating the Internet."

His running mate may be raising the ire of scientists with her positions on creationism and wildlife conservation, but Republican presidential nominee John McCain is touting his tech cred. In a page out of the Al Gore playbook, McCain boasts that "under my guiding hand, Congress developed a wireless spectrum policy that spurred the rapid rise of mobile phones and Wi-Fi technology."

McCain's remark today was in response to 14 science-policy questions posed to him and Democratic opponent Barack Obama. The Arizona senator's replies are published online by Science Debate 2008, a group of science and business leaders. (Obama answered the group's queries about three weeks ago.)

Newly minted Republican vice presidential nominee Sarah Palin has made clear she's open to teaching creationism in public school science classes and to oil exploration in the Arctic National Wildlife Refuge (ANWR). While her running mate, John McCain, has spoken up on some science issues (pro-off shore drilling, anti-opening ANWR to oil exploration), less is known about his positions than those of his Democratic opponent Barack Obama, who recently answered a series of questions on everything from climate change and energy to stem-cell research.

Some highlights: Obama says he would lift a ban on federal funding of research on embryonic stem-cell lines created after Aug. 9, 2001 -- a measure signed into law by President Bush, who vetoed legislation designed to lift the limit. Obama also supports genetic engineering of plants and "water smart" landscaping over irrigated lawns to conserve H20, according to his responses to questions from Science Debate 2008, a consortium of Nobel laureates and business leaders.