I'm guilty of being one of those who have switched to sending e-cards instead of actual cards for pretty much any and all occasions. It's just easier, more inexpensive (I mean free), and allows for last minute sending. That last part is especially useful if you remembered the occasion only a day before or even on the day itself! =P
But of course, I'm still a bit choosy even with e-cards. There's a lot available out there but I don't want to send just anything to everybody. There are still factors I'd consider including whether I like the e-card and whether it suits the person I'm sending it to. Also, some of the nicer ones aren't freely available. So anyway, I usually end up going through site after site after site of e-cards before I find the one I choose to send.
This Christmas, I set out to look for a Christmas e-card to send and found this unique, ingenious one. =)