I know it's always been pay to play on the radio but In Drake's case I think it was organic, and completely driven by the internet. Drake became hot when sites like mine, Nahright, 2 Dope Boyz, Smoking Section, Concrete Loop etc started covering every single thing Drake was doing, between those blogs and along with others on any given day Drake was getting exposed to over a half a million people easily.
And Drake is not some overnight success, HipHopmUsicDotCom.com and a few other sites have been covering Drake since late 2006.
I do agree that now that Drake is in the middle of a 2 million dollar bidding war, the labels are most likely paying to get his record played to get him to sign to there label, this is nothing new.
Drake's buzz is real though but definitely nothing like 50 Cent's buzz, since 50's situation was so different he was in a life or death situation which made him more interesting it wasn't just about the music.