As of now, it still works for me exactly the same as I described above, except that I started seeing the occasional adsonar ad on viewtopic, which is working fine for the most part. However, I clicled adsonar's wine baskets ad (which is a default, rather than relevent ad), and that link brought me to
http://www.able2know.com/cgi-bin/links/jump2.cgi?ID=989 , which only showed the portal saying "Oops, we had the following problem: Cant find ID number:". However, following that link I just posted here works as intended...the site loads fine, along with your 'rate this link' frame on the top...but I can't get the wine baskets ad to load again in adsonar in order to check if the link messes up every time from there.
By the way, the z1.adserver.com ads that I mentioned in the first post (which work fine), are displaying on the bottom of the posting.php "Your message has been entered successfully" page, which is weird because it's always the same exact ad as the fastclick ones I see on the top of that page (which incorrectly send me to ebay).
All of these problems are perfectly consistent for me, as far as I can tell.
Gimme a day & I'll see if I can duplicate them on another computer.