This development is welcome but poses many questions. They will have to offer many more titles than the limited number of hi-rez offerings on their current site. IMO they are going to take a hit on the current site since you will probably get a month of hi rez streaming for what they currently charge for 1 to 2 downloads. (Sure there will always be audiophiles who prefer to "own" rather than rent their music, but that number is dwindling.)
I think this shows if you want to survive or participate in the music market beyond that which caters to the niche audiophile segment, streaming is a must for the future.