I think their indication will be proved right. I think other indicators will start to reinforce this. The quality of the competition's products - especially search - are developing apace and I think Googke is trying to diversify in so many different ways at once that they might start to lose the hearts and minds battle.
This I see as less likely.
But as Techrealm says... we'll see in six months. That'll be Christmas and we'll all have good ROI data across the big three (in PPC, that'll be the first time we've had all three). The ROI data will start to shape the market share - as will vista and live.com of course.