The Taekwondo Wikipedia article says:

"Gup rank advancement records are kept by the school of origin, and sometimes by the style's association headquarters. For Kukkiwon practitioners, all ranks of 1st Dan and above must be registered with the Kukkiwon if the black belt wishes for his rank to be acknowledged at other dojangs, or if he wishes to participate in the Olympics. A "Wallet Certificate" (which looks like a photo ID card) is commonly used by practitioners when they attend tournaments or transfer schools in order to certify their rank."

Is there a standard form of this wallet certificate?

This is pure hogwash...they are just trying to sell you a card to make some cash. Don't fall for this. No tournamenort cares if your a black belt, especially local tournies. If you got the cash your in. Usually because you sign up with a school, the owner or teacher makes sure his students are registered to the WTF. For me I've never had to register, my teacher takes care of it for me. When I attend tournies I don't pay I get in as a coach.

Some national associations issue their own black-belt cards (credit card size) as well as instructor cards. Sometimes they do carry the WTF/Kukkiwon insignia. Check with your instructor or association.

Do these things allow you to pick your blackbelt up if you happen to have to go to another TKD school?

I never leave home without it:

Haha Ed, that one's priceless. I think I'll get it printed out and make my own Nobody'll mess with me!!

Martial arts + marketing = no shame