What does Hov have to do with Jay Z?

Answer 1

Thats a great question and I never thought about it until you asked but i found the answer for you:

First, you can see on the first line that Jay-Z refers to himself as HOV. He's not talking about being a high-occupancy vehicle, but rather HOV being the latter part of Jay-Hova, his self-given nickname. Jay-Hova is a play off of "Jehovah" which is a "modern mispronunciation of the Hebrew name" of God. So by combining his rap name and an ancient name for The Mighty One, he is, essentially, calling himself the God of the rap game and its culture.

http://phark.typepad.com/phark/2004/04/jayz_explanator.html