You should take a look at TagCoin. It's the first real business enterprise I've seen behind an alt-coin with 17 staff and they have a (I think) fully licensed and regulated fiat-to-BTC or fiat-to-TAG exchange, and their rewards platform is quite extensive, if you are a developer you will notice the work that's gone into it.

https://bitcointalk.org/index.php?topic=317408.0
About page: http://tagbond.com/site/about
Exchange: https://trade.tagbond.com/

Also you're welcome to join the giveaway I'm running https://bitcointalk.org/index.php?topic=327652.0