After sending a campaign, I noticed a lot of clickthroughs from hotmail.com addresses this night. The clickthroughs seem to happen fairly evenly roughly every 5 seconds.

This is for a list where opens are overwhelmingly happening during the daytime, and this sort of behaviour looks suspicious. It looks like Hotmail might be prefetching and/or scanning the links in the mail, at least that's the only explanation I can think of.

I did a search through the forums, but couldn't find any mentions of this issue. Has anyone else experienced anything similar, specifically with Hotmail?