Hmm really he's suggesting that the AM3 Thuban is better then a 1366 i7 950? maybe it is given your budget....but not in benchmarks....and there's no upgrade path when you buy the most expensive processor for the given socket.
Really the best answer is ......
1.) If you can send what you bought back do so and buy a socket 1155 motherboard and i5 2500k.
2.) If you can't send it back and have a Microcenter near by (or a friend that lives near one), buy a i7 950 for ~ $200.
3.) Otherwise, follow mosox's suggestion.
Edited for typo