New west coast vibe that'll get you lifted check Rae out!
east coast hip hop doesn't have a distinctive "sound"...per say; or rather, not one that is congruent throughout. whereas west coast can be categorized as g funk, or having funk elements and synthesizers, east coast is more about flow and lyrical domination. domination, as in dexterity, battles, etc.
i think east coast is "more grimey" or gangsta, but that's just my opinion. west-coast had tons of gangsta rappers...but east coast (imo) is much more raw, not as synthetic.
hip-hop started on the east coast and if you listen enough you'll be able to pick artists out by where they are from. sounds vague and lame, but i can do it.