You can peel off the top layer of the tape until only a thin clear layer that looks a bit like scotch tape is left.

Goof Off (latex pain remover) works good on a rag with some elbow grease to remove the last bit of tape and is Zipp approved for their wheels, Home Depot carries it, check the paint section.

And regarding the tape, remember once you have experienced removing all of that residue that if the original tire had been glued on with something like Vittoria's mastik one you would have only had to put some glue on the tire and rim after you removed the old tire and you would have been done. That is quite a bit less work in my opinion than removing all of the tape residue.

I think any time saved by the tape in initial application is lost when it comes time to change the tire or re-tape. It does hold just fine though and it works, at least on tires with the right type of base tape.