shorebreak - 5:57 pm on Feb 24, 2008 (gmt 0)

Brett, I'm surprised to hear you say that it's a great way to guage performance of keywords you haven't tried before. 'Great' would imply that Google has a high probability of finding keywords with good ROI, yet this new feature appears clearly to have a #1 goal of spending unspent budgets.

I do agree that *some* advertisers who are opted in to this feature will find *some* good keywords in the process, but I think the history of EBM , Conversion Optimizer and CPA-based content network buying is not one replete with pro-advertiser outcomes. The advertisers who kick a$$ on AdWords do their own homework, leave nothing to chance and optimize with full visibility into ROI - and that is unlikely to change.

For anyone who has more details on this imminent beta, I'd be very interested to know if the plans post-beta are to make this opt-out or opt-in.