After reading this thread, I've come to the realization that "Mob Muzik" is a loosely defined term.
Some people define it as a sound (i.e. Mike Mosley/ Sam Bostic type production. Live instruments ect.)
Others (like me) define it as a feel. Growing up on (and being a big fan of) artist like C.I.N., A.M.W., C-Bo, Killa Tay, I define it as: Music with a dark feel that is created for and or inspired by MOB LIVIN'.
I only named 4 artist/groups above, because these are the only niggas I know that have had FULL Mob albums from front to back, inspired many other up and coming artist, and spit bars that have been used, re-used and reworked time and time again. In fact today I just heard a Beeda Weeda song where he uses the line "The funk ain't ova 'til somebody die!!!" from the classic mob track Agent 187.
In my opinion, Mob Muzik is only the records with a dark feel to them. That's why no mention of E-40. Many of you will surely think it's ridiculous to say that Forty ain't Mob, when to many he's not only the poster boy of Mob shit, but also the definition. But Forty has never been a dark rapper.
I'm not dissin' Forty. I think that he's one of the rawest MCs from the Bay or any where else. I just think his stuff is too light to fit on a playlist that I would call "Mobb Muzik". He definitely laid the the ground work for this shit, but he's always been playful with it.
Mr. Flamboyant is a Mob-like track, but Mr. Nonchalant is a 100% MOB SHIT!
But at the end of the day, it's really more of a matter of opinion. A lot of artist these days actually believe that their making mob shit, just because they tote guns and holler out "Mob" every other bar. That's their opinion of "Mob", above is mine.
Another notable mention: 2pac. A lot of his unreleased (untampered with) material is some classic Mob shit.