The distinction isn't between music and BS, it's between BS and things that aren't BS, which needn't necessarily be music. For that matter, it's perfectly possible to have music threads that are BS, though normally they aren't so labelled, and they tend to wind up in the top end of the page.

One interesting thing that the split brings out is the fact that there are so many more threads which are music than BS. I think this has always been the case, and that the common false impression to the contrary was because threads tend to get a steadier stream of responses when a discussion is active, so such threads tended to cluster up towards the top.

On the other hand, I suppose it's possible that the new arrangement is changing the balance between the two sorts, and increasing the number of music threads. Anyone feel like researching which is the truth? (For example via this time warp facility.)

And thanks Bee-dubya-ell for passing on that de-splitter - I'm with Greg in preferring it that way, so I'll bookmark it now.