I was looking at the Umixit site. There doesn't seem to be that much going on in terms of new music being released on that format.
I tried to order a few CDs from Webster Hall, but they wanted USD40 for international shipping - which is a bit over the top (I'd want to be ordering a whole box of CDs to justify that sort of shipping cost - Amazon charge about USD10 to ship from the UK to NZ). I might just grab some when I'm next in the US.
A pity, since the idea of a Cakewalk based system looks promising.