Kudo Tsunoda, Don Mattrick and John Schappert went from EA to Microsoft.
Peter Moore (anyone else?) went from Microsoft to EA.
One could argue that their making good switches, going from one large company to another, and not losing position in the process. One could argue that because of what they do, they already have good relationships with the other company and capitlized on that. Could be they're quite familiar with the other company too; EA supports two Microsoft platforms after all (Windows and Xbox 360).
But it just seems... I dunno, weird. Not incestuous or anything, but still, wierd.