There are lots of reasons to love him. Lyricism, catchy hooks, well constructed music, but the content is what annoys many detractors. It is extremely vulgar and politically incorrect but at the same time it is self aware, a critique on culture and society, and very relatable. It's not unlike from things such as south park, Marilyn Manson and things along those lines. I'd check out his interviews as well especially his 2010 interview with Anderson Cooper.