I think the great community is reward enough. Everyone is so friendly, and even the bitter and snide people are usually not that bad.
My first sense of being rewarded was seeing that I had earned my first dollar. Along with that, one of my Hub was considered a HubNugget/Raising Star Hub. It felt great because it made me feel like my content was actually being looked at and that it actually matters. Although I didn't win any sort of contest, I still felt like I had done something great! 