yeah it's funny, sometimes it doesn't want to make you an ultrapeer, sometimes it does. depends on demand apparently (?). but you don't necessarily want to be one, it increases your bandwidth use a lot (though not alot, a lot, it's pretty reasonable... i had over 100 connections ealier and it was at only erm 25% capacity - whatever that means lol). but it also seems to increase your results a lot... haven't really played enough to be sure yet. of course, it matters where you get into the network, and that's pretty much pot luck with gnutella for most people. Staying online for a long time definately helps.
maybe i just got lucky before lol.