Predicting who will win Nobel Prizes is a tricky business. The Nobel committees' nomination and selection processes are cloaked in mystery.

Each year, though, a couple brave organizations try their luck. One of these is Thomson Reuters, which has released a list of Nobel picks every year since 2002. Thomson bases its picks largely on the citation data that ISI - a part of Thomson Scientific founded by The Scientist founder Eugene Garfield - collects. Thomson has correctly picked 12 Nobel Laureates, and last year five of its picks won Nobel Prizes. Many of these winners, however, were picked by Thomson years before they actually won their prizes. David Pendlebury, a bibliometrician with the company, said in a teleconference today that he compiled this year's list of "Citation Laureates" in September. "They seem to be peers of people who have won the Nobel Prize in every way," he said. "They're of Nobel class."

This year, Thomson picked three teams of researchers to win this year's prize in physiology or medicine. Shizuo Akira, an Osaka University microbiologist, Bruce Beutler, a geneticist at The Scripps Research Institute, and French Academy of Sciences president, Jules Hoffman make the list for their work on innate immunity and toll-like receptors. Victor Ambros and Gary Ruvkun, two researchers at the University of Massachusetts Medical School and Harvard, respectively, who discovered and studied how microRNAs regulate gene expression. Ambros and Ruvkun won this year's Lasker Award, a good predictor of Nobel success, according to Pendlebury. The physiology or medicine predictions are rounded out by a pair of University of Oxford statisticians, Rory Collins and Sir Richard Peto, who revolutionized clinical medicine and epidemiology by devising and applying meta-analysis.

The company has named three scientists that have a shot at the chemistry prize: Charles Lieber, a Harvard chemist who conducted some of the early research on nanomaterials, Krzysztof Matyjaszewski, a Carnegie Mellon University chemist who developed atom transfer radical polymerization (ATRP) and other methods designed to rapidly and efficiently join molecules together, and Roger Tsien, the University of California, San Diego biochemist, who first used fluorescent proteins as biological probes. Given the interdisciplinary nature of his work, "I wouldn't be at all surprised if Tsien won the prize in medicine," said Pendlebury.

The Nobel Prize in Physiology or Medicine will be announced on Monday, and the Prize in Chemistry on Wednesday. But in the meantime, we've set up a poll using Thomsons' picks at the social prediction site ZiiTrend. See the windows below, or click here to weigh in on who you think will take home the physiology or medicine prize and here to vote on the chemistry prize.