I really think that you guys underestimate the meaning of mining as an awesome marketing instrument of bitcoin-like technology.
A lot of people started using bitcoin because they just had it out of mining (me included).
And not because they needed it badly to buy weed on SR.
My GPU was mining litecoin 24/7 when I got into this more then a year ago.
And I STILL COULD DO MY DAILY photoshop/html job on my pc while gpu mining.
If the mining will be CPU-only some random dude will not be able to mine and work on a pc simultaneously.