Don't worry about the people down here, we're an antisocial bunch - most of the time...
As for the avatars, stock forum avatars only until 100 posts. I've seen that policy in place before on two or three other forums, and it actually makes a lot of sense. Allow me to explain...
Avatars come in two flavours - normal and animated. An animated picture is actually a series of pictures, each one very slightly different to the last, and this gives the illusion of motion - hence, animated avatar. Only problem is, is that a normal avatar is ONE 80x80* image, while an animated avatar is a series of 80x80 images. More images = more bandwidth used = higher costs (bandwidth ain't cheap). As it happens, custom avatars will use extra bandwidth in any case, and animated ones more. Slight, but it adds up.
Hypothetical situation - someone joins, posts twice, selects a nice custom animated avatar, posts three more times, and disappears for whatever reason. So now the webmasters have to deal with extra little pictures that consume extra bandwidth. The 100 posts limit is supposed to lessen this issue, apparently.
*80x80 pixels is the largest available size on this forum.
By the way, the above paragraphs aren't the real reason, I just don't know what the real reasons, if any, are.