I think they should do kinda special playlists say 1 week a month or something, based around different themes but the same thing all the time would get as boring as if it were regular playlist.
Rap music week will be fun.... not 
Err I LIKE rap... among many other types of music, I've kinda adopted an ethos John Peel would be proud of when it comes to music, give everything at least one listen.
maybe a few days a month, a whole week would be too much.
Anyone who thinks we're contributing to the dumbing-down of internet forums can shove their stupid opinion up their a$$