I'm on the Pono train, second wave player due in December. I like that it's a one stop shop. Uses the iTunes model without the proprietary nature that Apple perpetuates.
I like the traction gained to this point, and the way it's apparently run. Recently announced it's bringing JRiver on board, I'm there as well, so it looks to integrate well with what I have and am accustomed to. During the crowd funding they had the foresight to get artists on board, which looks like a good move. Certainly was well funded at onset, which should result in good launch and hopefully healthy life.
I'm rarely an early adopter, but just felt like the timing and product was right.