mctrivia: I've been thinking about that a year ago. But:
1) Not all browsers support Ajax and the noscript solution would only make the page code longer.
2) If someone updates only a part of the page (e.g. game board section) and does it continuously for, say, an hour, he would not be aware of other important information like the number of new messages etc.
3) JavaScript based code is much more error prone than a simple HTML, so it would take more time to make it stable. Not to mention other server side changes which are necessary to make it work anyway.

Fencer:
1)Yes Ajax is not universally suported but is almost.

2) If you encapsulate the different parts you want to update into there own subroutine then use javascript to update each you can have it put out raw html witch would require few changes to the sight.

3) Overhead of using noscript is very minimal. If they have scripting you put in the ajax code set to run every 30 sec. If not then you are still using the same subroutines to create the page just not adding the extra java script to allow it to reload in the background and using the meta reload instead.

It is a little bit of extra work but the visual improvement of not having to reload the page as well as the bandwidth reduction by not downloading parts not used would vastly improve this site.

mctrivia: I am not totally up with Matthew on this (as you know welll lol), BUT if it could help in the long term of page loading / updating it could well be worth looking into further

Maybe you and Fencer should have a talk about it, and it could be your project