I'd personally go and sell, but only as Apple's focus will be on Intel so at least you'll have a good base to move forward on. I can see a point not too far in the future when PPC code is no more and apps developers will focus on Intel only.
You do raise an interesting point though around buying Macbooks - I've never really considered buying a laptop as a slave as I always saw the cost as too high when you can buy 2 minis or an iMac for the same price. Why not buy 4 x 2GB mini's and control them with leopard's screen sharing?
And I do wish VSL would lift the veil of silence on all this - or at least give us a countdown on the front page.....