It's not that I doubt you -- no, not at all, because I have a copy of the original, so it's clearly a vector -- but, damn, is that really Illustrator? O.O This is why I will never be a real artist. No patience to figure out how the hell to make that software do my bidding. >.< Also, it's a small thing, but you win my respect for leaving his signature on it. Excellent job, a perfect tribute.
Patience is a virtue - especially when you're dealing with Illustrator. People want me to tell them how to do these, but there isn't much I can say other than to just open the program and fiddle with it until they've figured it out.