That's a tough one...Cube did advocate their beliefs and literature (esp. the book MESSAGE TO THE BLACK MAN by Elijah Muhammad) during '91/'93, and also had members of their security (The Fruit of Islam, AKA F.O.I.) working for him as bodyguards. From what I've read and heard, Cube was introduced to the ideas of Islam by Shorty and Kam, two former gangbangers-turned rappers.
Whether he's actually a member, I'm not sure, though...Rolling Stone Magazine's NEW BOOK OF ROCK LISTS has him listed under "Followers of Islam" in their "religion" section. On the other hand, Muggs from Cypress Hill once said, "that Muslim shit was fake. Cube goes with whatever's hot." Don't know how much stock I'd put into that statement considering that it was made when Cypress was feuding with The Westside Connection! LOL!
BTW--THE GLASS SHIELD's not too bad. A little slow, but interesting here and there.
PEACE!