This has to fall under the category of "Geek Magic" more than anything else, but if you're a fan of that sort of thing it works. In essence, you are making your finger do things it was never intended to do, and if you practice enough even those with strong stomachs will cringe.
I could only find one thing that I saw he could have instantly improved upon but chose not to for some reason. Meir Yedid's "Finger Fantasies" is credited here for the beginning of the routine (making the pinky finger appear to disappear into the hand), but Will takes the second part of the routine (a complete pinky vanish) into material that he created for the move. Unfortunately, it's the weakest part of the entire thing because it's instantly obvious to everyone what you're doing. Instead, he should have followed through with Yedid's second move in "FF" to accomplish the same thing in a much cleaner way. It can actually give a shock and awe moment just before you make it reappear. From that point on the routine is superb and very nice for a time when you don't have any magic on you and folks want to see something. If you want to really turn this into something that can go about five minutes or more, I would suggest getting "Finger Fantasies" and combining it with this. The combination is a natural. Finish this off with the "Arm Twist Illusion" (also available from Meir) and you can have a lot of fun with a spectator using no props whatsoever.