How NOT to do a holiday card -- if you're planning on sending an eCard to your list of customers and prospects, send the card in the email itself as an HTML or rich media email, instead of using an eCard service that requires that people click through to "pick up" their card.

Why? Well, I'll bet few people will bother click through. Especially once they have gotten more than 3 messages from various vendors and businesses telling them, "Click here to see our card for you." Instead of looking warm and caring, you look cookie-cutter and chintzy. You've just told me I'm not worth the expense of a printed card, and you're going to make me work to go pick something up that's obviously being mass distributed to everyone who's not worth the expense of a printed card.

This type of eCard does have its place when used on dates of personal significance such as birthdays or to congratulate someone on something they've just accomplished (a new baby, winning an account, a great SEC filing, whatever). But when used to mark mass holidays they completely miss the boat.