I installed Google Toolbar two days ago to see how BlogThis! works.  Not bad for a first cut.  While using it, I noticed the Popup Blocker.  In the past two days, it block 37 popup ads.  Yesterday, I had to override the blocker to access some Comcast popup windows.

IMHO, popup window is a bad design choice.  It is unfortunate that 3D-Secure accepts PIN in a popup window which just opened a can of worms like conflict with popup blockers.  But it was a marketing decision and you know how little leverage engineers have over marketing decisions.

Anyway, I just thought it was interesting that Google doesn't do popup ads and its Popup Blocker have the potential to degrade effectiveness of popup ads sold by others.  I am sure Google engineers added this feature with only the Google users' benefit in mind (engineers are incredibly innocent by nature), but I think the effect have the potential to be become significant if Google Toolbar becomes really popular.

Just in case Google-haters misuse this post, I want to make it clear that I like using Google the product and respect Google the company's good intentions.