This Oscar thing has been back and forth for a couple of days, but reports out of Brazil would suggest that it's nearly done at this point. Globo Esporte had the following:

Oscar arrived in London and went straight to the home of Chelsea. Still at Heathrow, the player was released by the Brazilian team to conduct medical examinations in English club and sign the contract. The official announcement should happen in the coming hours. The British press reported on Tuesday that Chelsea paid £ 25 million (U.S. $ 79.2 million) by the Brazilian.

With all of the back and forth on this one, I'm a bit hesitant to believe this rumor. It's certainly worth a mention though, as we know that Oscar was set to arrive in London today in advance of the 2012 Olympic games. If true, this is some pretty exciting news for Chelsea as Oscar is a fantastic young midfielder. Here's hoping, right?