RSS stands for Really Simple Syndication in computerese! It basically creates a bookmark that updates a list of entries each time the site is modified - used for news feeds and the like.

If you go to the page that lists all the different forums, you'll notice that in brackets next to the forum names it says (RSS)... click on RSS and you should get some kind of message saying do you want to subscribe to RSS now - in firefox, it asks you where you would like to place the bookmark (you can put it in the bookmarks list, or the bookmarks bar - the bar is most useful for a quick look at what's happening on the forums). I presume that IE7 will have some kind of similar setup - I use a mac, so don't have internet explorer to try it out - there's some info on microsoft's site - use the link below.

http://www.microsoft.com/windows/IE/ie7/tour/rss/

Cheers
Luke