Essentially, it's easier for some genres (reggae) to be posted than others (rock)
I'm unsure if the addition of sub-genres will further affect this.
I'm torn in that I think it's unfortunate that non-mainstream artists were disadvantaged in the previous system (If you're newish, a few months ago, all genres were treated equally), but I think it's unfair that a mainstream act has to be that much better in the current system.
I'll pick on Zuba (because I like them). If I recall properly, Zuba sat is relative obscurity for at least a week, maybe two. But then Hail Africa got posted on relatively few bumps (genres were reggae, acoustic [now folk]) and obtained that front page exposure. Now their most recent upload, Kuleh, shows 378 bumps after 1 day (so between 24 & 48 hours). That's great for Zuba, but it's obviously not as great for more mainstream artists. I'll pick Zsammy (same reason). The songs garner around the same number of bumps as Zuba, once posted, but they take are significantly harder to post (at least the ones categorized alternative, rock do). Anyhow, he's stuck a few points away from level 7, so I'm going to go fix that.
So the short of it is. I think the disparity is good & bad. How's that for a decisive answer.
I'm curious as to how other people feel about this, so comment away....