Java can raise compatibility problems, eg. I beleive this one isn't too great on some macs.
It also won't work for WebTV although I have little tolerence for those things and quite frankly fail to see why computer efforts should in any way be dictated by what is not a computuer can not do (or is it 'cause mr gates does not control Java)
I'd not use the server/browser refresh system at folkinfo for reasons of bandwidth (and I can do this without touching my resources except for access to get in) but it's not only that - I don't believe in trying to make an HTTP server into a chat server this way as these things request pages to every user on line every few seconds.