Since the advent of affordable camcorders (and now digital recorders), couples have enjoyed making movies of themselves engaged in various behaviors, including sex. It certainly can be a great turn-on, sort of like making your own personal porn flick.
There is no harm in videotaping yourself and your husband engaging in sexual activities. Of course, some couples are surprised by what they see. Few of us look as good as the porn stars who are carefully made-up and filmed under perfect lighting. Plus, most individuals cannot keep up with the sexual athletics of these professionals. Just keep a good sense of humor, and remember that comparing yourself negatively would be akin to making a home movie of your family playing basketball and then being embarrassed that you can't shoot as well as Michael Jordan.
The biggest thing you should be worried about is what happens to these tapes. It is not unheard of for people to accidentally return the wrong video to Blockbusters or NetFlix, or for kids looking for a blank tape to stumble upon mommy and daddy swinging from the chandelier. I highly suggest that you lock up your tapes in a secure place and make sure they are well labeled and kept track of. You also might want to make a deal with your spouse that under no circumstances will either of you ever make a copy or do anything with these tapes without the other's permission.
But aside from these safeguards, enjoy yourselves and just hope that you don't have a nasty divorce and find your face (or much worse) plastered all over the Internet.