Just recently happily updated to Spybot 1.6, but noticed massive slowdowns in IE7 when opening IE7 for the first time, and opening any new tabs. It could take literally up to a minute. This also coincided with the most recent Windows Update, so at first I suspected that. But then I ran IE7 without any addons, and it worked flawlessly as before. Doing trial-and-error I uncovered that the two Spybot addons were responsible for this effect. This is with both Vista and XP.