I'm terrible at sending cards, and I find it a nuisance. What's worse though, is that my mum gets cards and she has NO idea who the people are. She may have met them once, or be related to them, but if they sign the card with their first names only it's hard to guess. She gets a few like that every year.
I go through the ritual, but only because it's generally done. But awkward situations sometimes come up. Should I send a Christmas or birthday card this year to my lately ex-sister-in-law? At what point should a Christmas card to my brother also be addressed to his new partner?
We did get one christmas card last year that said that they would not be sending cards this year, but would be making a donation to a charity (I think it was for MS) instead. Sounds good to me! We did that in work too - everyone gave a couple of pounds and we gave it all to a charity instead of giving out cards.
Why do people have to know one is donating to charity except to inform them what a Wonderful Person one is? Why not send cards as usual and donate to charity? Or send "charity" cards? I normally send cards to people I don't see very often; it just means you've remembered them and value them. Some, but not all, of a group of pub mates have taken to sending (i.e. dishing out in the pub) Christmas cards to each other, which I think is barmy. I don't do it and it's done me no harm whatever.
I was firmly in the anti-card camp, but I've found things have changed since having a kid. Suddenly photos of the littleun are a commodity for relatives - especially the older and less internet savvy kind. So, I've been sending cards using pictures of my son to people where in the past I might have a) sent a crappy off the shelf card and hated the whole process and b) not bothered through apathy.
One thing that kick started it all was finding a program called Comic Life (Mac users - I recommend it heartily) which is great for knocking up comic strip style cards using my own photos. I've also been known to send an occasional e-card as a slightly more colourful way of marking an occasion than just sending email. I think cards for me inhabit a sort of middle zone of contact with someone, and I find it pleasing to think that I can send my offline relatives something tangible with a picture of their grandson/great grandson on it.