Admittedly I haven't read the code to see how the algorithm weights things, but on HN a high number of comments seems to downrank stories if anything. This site is so low-traffic in comparison that IMO it would be really nice for a new comment to bump a submission to maybe the bottom of the front page or top of the second, sort of like an oldschool web forum. The way it is now I feel like commenting on anything beyond the first couple of pages will never be seen.