As Bitcoin continues it’s growth lots of people will try to start their own Bitcoin clone. (Here’s a list http://dustcoin.com/mining ) Novacoin is one of those new coins. You may be interested in some of the background of this new crypto coin. It appears that the people behind Nova coin pre-mined some of the coins. This to me is totally unacceptable and should ring alarm bells for you.
Here is the post for Novacoin from the bitcointalk forum
A bitcoin exchange was also implicated in the dubious launch of this coin also, read this thread too.