Canadian newegg links behaving badly

How does this work?

It's Firefox with ABP and noscript running.

If I click on ANY newegg.ca link I am taken away from the page I'm viewing and end up at newegg.ca home page. At the same time a new tab opens but is blank. The blank page seems to have the URL of the thread I was viewing, but the URL of the newegg.ca page looks like this:

[cpp]http://www.newegg.ca/?nm_mc=AFC-C8junctionCA&cm_mmc=AFC-C8JunctionCA-_-homepage-_-na-_-na&AID=10593543&PID=4176827&SID=uoniq3asmmh9[/cpp]

Here is the thread where I first noticed it. His BBCode looks fine, I edited his post while I sort this out.

http://www.tomshardware.com/forum/315639-31-budget-gaming-computer-feedback