some other pretty good stuff is sage francis, brother ali (dope as heck), living legends (scarub, eligh, grouch, atmosphere, that whole groupie), cali-MHZ, people under the stairs (nice jazz/hip hop fusion), Chi town- Copywrite, Jakki da Motamouth, michigan- Binary star (amazing music, one of my favs), freestyling- sage francis, supernatural, canibus...too many artists out there.
mainstream- im listening to the grey album by dj danger mouse. He took jay z's black album's lyrics and the instrumentals from the white album of the beetles, and made the grey album...really amazing stuff.