Well, this is an interesting tactic. The major label boys now believe that waiting to sell digital versions of songs until after the brick and mortar release will increase full album sales.
I won't pretend to understand the laws of supply and demand. I don't. But as a simple consumer I think there is probably something attractive about the waiting game. If you dangle this new music just out of my reach and build a buzz, I'll probably salivate for it more than if it's readily available in pieces. This tactic does make a release seem more special somehow.
However, I would remind these folks that if you do this, you'd better be ready to provide (1) a quality album of music, not just a single and junk, (2) something to hook the generation of kids who aren't attached to album artwork and (3) a bargain price. Otherwise you'll be dealing with a mighty backlash of pissed off kids who will head straight for the songs on illegal P2P sites, not because they don't love music and want to cheat their favorite artists, but because they've been disrespected as fans. Wait a minute, didn't all this already happen? Major labels are trying to go back to the future.
I understand that they're trying to hold on to a business model that worked for them instead of giving way to one that doesn't. That's corporate survival instinct. To me, though, it seems stupid to hang the major label hat on the CD album format when it's sure to end up in the bin with cassette tapes. CDs don't offer superior sound quality. Most people are listening to music not out of their 10 speaker perfectly equalized systems but out of cheap computer speakers. Those who care about sound quality are probably into vinyl. The only thing that keeps me hooked on CDs is the liner notes and nostalgia, but in fact basically every band website provides more info than can ever fit in an insert.