30 days ago, BellKor Pragmatic Chaos submitted a prize-qualifying entry for the Netflix Prize. According to the rules, competitors had until today to submit a superior entry, and rivals The Ensemble met the challenge this morning with a new submission that rocketed them to the top of the leaderboard. BellKor appeared prepared for such a challenge, though, and submitted a tying entry with just 20 minutes to spare. But it seems The Ensemble faked them out: with just 4 minutes to go they submitted a new, better entry, leaving them in first place for the million-dollar prize.
Update Jul 27: BellKor may yet have won. From a commenter on Reddit:
The way the Netflix Prize works, the test (quiz) set was split into two portions to prevent people from gaming it: half is used for the published results on the leaderboard, half is for the actual prize. Team BelKor has been in the lead for a long time, but was passed yesterday by a combination of the second and third teams called Ensemble. BelKor caught up with under an hour to go before the deadline, but with only minutes to go, Ensemble submitted another result that put them on top of the leaderboard by 0.0001. However, this just reflected half the test set, and the other half is what counts. BelKor team leader Yehuda Koren posted on this thread that he was contacted by Netflix and told they have the best test accuracy and should be declared the winner.
TechCrunch: By A Nose: Netflix Prize Leaders One-Upped With One Day Remaining