Personally, I do not like gift cards. They show a lack of thought and consideration. In my opinion.
I'd rather get an ugly tie than a $20 gift card to a mall that will only buy me a piece of the sales tax. Of course, I'd PREFER an 18 volt cordless DeWalt hammer drill (hint hint
) but if one MUST give a gift card (think troops overseas or otherwise unreachable relatives) at least give enough to buy something decent at the location that you buy the card from. Malls IMO require $50 minimum due to the pricing structure there. One good book at Waldenbooks or other bookstore costs around $30 - $50.
My position is to try my best to give a gift that shows I was thinking of the person and that I cared enough to remove the price tags and wrap it (or have it wrapped...no one has yet complained after they see my appalling lack of wrapping skills) and add in accessories if required. Batteries in the package with a portable stereo is a nice touch, as is candy with a candy dish. Or something like that.
Your mileage may vary, but I think I hurt more feelings with a card than a vacuum cleaner (yes, I've done that, unfortunately)
Brian