The London Chess Classic will either start Wednesday, or has already started, depending on your interpretation. Right now they are playing a FIDE Open event (round 2 will likely start as soon as I post this entry), and the top 2 after four rounds will qualify to play in the main event, the Super Sixteen Rapid. I guess that means they withdraw at that point from the open? Kind of a strange qualification process. In any case, the rapid features some of the top players in the world (including former world champion Anand, in his first appearance after losing the crown to Carlsen).
The players are sorted into groups, ala World Cup format, and will play within that group for the first 6 rounds to determine the winners of the group. The group winners then go on to the playoffs, to finally determine the London Classic champion. Here are the groups:
I suppose one can argue that the best of group A and D get an easier road to the playoffs, given they have a cannon fodder qualifier in their group. Although Nakamura must be the favorite to win group C anyway.
The FIDE Open features two American players; IM Justin Sarkar and untitled Mariano Acosta.