Synchronized now. Anyone else? At block 2159.
Yes. You can do a 'getblockhash [block number]' and it will give you the hash for that block. If others match the hash then you are all on the same chain.
getblockhash 2159

00000007e81162009cd374682213139c1a9f78b513dc4c1c2236c285b87b2f58
hmmm...