I found that groups.google.com can take many hours before you see a
post you have made.
I really like the web based interface, although I would like to see
the enhancments suggested by Michael the last time this came up.
(Especially the one where it remebers my name and email address, its
tedious typing it in all the time.)
I tried to use netscape 7.12 newsreader for a while, but I like the
way you see the whole thread with the MathWorks web based one and at
the same time when you click on a post, so there is an instant
history, but you also have all the posts sorted in chronological
order. With the newsreader, you could group by time OR thread, but
not both simultaneously.