So far I have stuck with Smashwords and Amazon for ebooks, and then I have print on demand with lulu.com, but so far only family members have ordered a non-ebook.
Smashwords opens up Sony, Kobo, B&N, Apple, and etc. My biggest movers are Amazon, Smashwords, and then B&N in that order. Amazon is on the order of 75% of my sales so far with Smashwords and B&N splitting the rest around 60/40 or there abouts. Sony, Apple, and the others do not even register on a graph....