Interesting bit from the Woebot link is the assertion that "the true medium of hip-hop is the 12"" Interesting cause it's true, but also cause I've often thought that it wasn't always true. Mind you I'm not an authority on hip-hop history by any stretch, but in the eighties (and early 90s?) wasn't it more of a paradigm for a producer to oversee/produce an entire album rather than the artist contracting out to multiple different producers as is the case now? It was/is impossible to think of PE without thinking of the Bomb Squad, Run DMC without Rick Rubin, Beasties without the Dust Brothers, De La Soul without Prince Paul, etc. Look at the liner notes for recent hip-hop albums and the same five names are scattered throughout the procution list - everyone gets a Neptunes track, a Timbaland track, a Kanye track, etc. Not that it's all bad, just different.
Also chipping away at the predominance of the LP in hip-hop is the ten guest MCs per album phenomenon which a) makes it frustratingly hard to pin down that track you just heard on the radio/in the club b) masks the fact that half of these cats can't carry an album on their own c) imbues upon albums the cheesy patina of a product launch akin to bad movie franshises/TV show spinoffs. "Oh, I'm supposed to buy this because he's a member of G-Unit, whose good cause they have 50 Cent, whose good cause he was picked up by Eminem, whose good cause he was discovered by Dre, whose good cause..."