Word is Emirates will finally serve the US in 2002. Flights will be non-stop DXB-JFK. Should also have service to ORD and probably LAX (not sure if non-stop for those). The 777s should work on those. As for the 3xx, it'll be a while, and I doubt they'd start 'em off on the runs to North America - would probably want to start slowly.
As for joining Star, they don't intend to right now - they'd prefer to remain independent.