This undoubtedly trumps the likes of CD Baby in many ways, but one reason I could see people sticking with them is that, even though to upload an album at CD Baby is more expensive up front, it's a one-off payment. You pay the $40 or whatever it costs, then that's it, the music stays up there at no further cost. From the DistroKid FAQ, if you stop paying your yearly fee then the music can be removed.
Clearly though such users aren't your target audience, you're going after the musicians that want to upload songs all the time, as opposed to albums.
Good luck to you though, this is the type of innovation this industry desperately needs.
TuneCore charges a (much larger) annual fee.