that number is really only the initial "seed"
in other words, the very first time I used that RSS link, my RSS reader (called google reader) displayed the latest 5 posts
but after that, all the posts are extracted continuously by google reader so that I am seeing ALL the posts since the day and hour i first subscribed. (which is exactly how i want it to behave)
FWIW, i personally prefer an initial default set to 10 for all RSS feeds
and I really like your solution : a global RSS feed on the frontpage and individual RSS feeds for each board
thanks
