This is because it is an rss feeed which is updated automatically and the forums don't control what it looks like, you can add this to your google homepage for example.
Sitepointstatic.com is just a seperate domain that points at an lighttpd webserver, its used for static content (images etc) to take some of the load off the apache servers that deal with the rest of the site.
The DNS entry for rss.sitepoint.com is a CNAME for pheedo.com (I think sitepoint use Pheedo for some RSS aggregation) - presumably this was done so that sitepoint could use http://rss.sitepoint.com/f/sitepoint_forums_recent as the address for their feeds, rather than the actual address (http://www.pheedo.com/f/sitepoint_forums_recent) It makes sense for SP to keep all of their feeds etc under the sitepoint.com domain.
Posting Permissions
Bookmarks