inbound - 3:57 pm on Feb 21, 2007 (gmt 0)

It WILL be in the next 48 hours judging by comments made on the AdWords blog and by AWA.

AWA intends to be around when it happens >>> Mon-Fri
The Blog still talks about this week (last post yesterday saying the update will be this week).

My guess is Google will want to run it tonight so they have time to correct any inadvertant 'issues'. I know they have the resources to correct issues at any time but my guess is they would prefer to iron out problems during 'normal' working hours.

More precisely, I'd say the switch gets flicked at 2AM (Google time), giving the machines plenty of quiet time to run through around 10% of keywords before engineers turn up on Thursday morning to assess the situation (with some engineers working through the night on it to react to any really big issues).

Remember, as we recently had confirmed, QS updates are not instantaneous, hence they should not be initiated just before most engineers have the weekend off.