I can't see any reason why they wouldn't be allowed, but from a reading perspective I wouldn't be interested in list threads as you describe them. Why should I care what your top 10 favorites are? Why should you care about mine? But if you explained WHY you chose your top ten, and WHY you ranked them in the order you did, that at least offers the potential for discussion, and depending what the topic is could lead to clearing up a misconception.
For example - and this is a made-up one - "I don't like The Gong Show because the panelists didn't take the acts seriously. And I remember one show where Chuck Barris introduced a Swedish contest as 'Sven - or Swen' whatever the guy's last name was, instead of taking the time to find out how to pronounce it correctly. Very disrespectful." Someone could post a response explaining that The Gong Show was done more for laughs than as a legitimate talent search and how everybody knew it - and that explanation might convince the original commenter to re-evaluate his feelings and watch the show with a different eye. You couldn't have that if the guy just included The Gong Show on a top-ten list of shows he hated and presented the list without any commentary.