I don't think it has anything to do with people being conservative on their bumping habits. It feels more like their is less activity on the browse pages. I know that I've been less active for a few weeks and although I consider myself as someone with a unique approach of music and play, it might as well be a trend. I don't hope so though, so I will try to get my act together and participate as I used to do.
@sumar: I always try to bump music I like. I always bump songs that I like listen to for the full song length. I used to bump every song that I expected to become popular, whether I liked the music or not, but I became a little more cautious with that strategy. I still believe I have to make some profit to either support the music I love, or climb a little in the Listener rankings. So, like Akatisia and others I'm in for the music as well as for the game. I don't have any moral issues with that, because, together with the social experience, they form the backbone of this site - at least as far as I'm concerned.

@Evonity: I am doing the same especially until today people were just not bumping. Look at all the songs that have made it to the home page with under 200 points.

I'm with Evonity - I just haven't been very active on the site for the last few weeks (this new project is kicking my butt... but "this job fulfilling in creative way"). That means that I go through and listen to/bump artists that I already know or that hit the front page, but I'm not trolling the up-and-coming pages much at all.