I think that despite modern electronics, business cards have a very important role and will/should take a long time to die off completely. Yes, there is an argument I suppose for why have them, they are just an expense and get lost and thrown away or ignored or are useless in any business arena, but this is an argument with which I disagree very much.
A business card is useful for all the reasons we know, it promotes and underlines who you are and what you do. I still think we see with our fingers, and a relevent card, well designed and explanatory with all the information clearly displayed is a joy for me.
If someone wishes to offer me a service and casually mentions "just go onto the web and look at our website, it's all there," I brush them off with a 'no, I won't,' and then look for another supplier. If they cannot be bothered to say anything more because they have a website (wow) and they are relying on me to do their marketing for them and then pay for their services, well then to me it's clear they have too many other things to do than seek or look after my business.
I have noted a development in print in that many trades people use A6 flyers printed both sides to promote and note what they do. This is also nice but still not as useful as a b/card, you can't tuck it away as easily.
Okay. So now I will step off my soap box and smile and relax and all those good things.
The next subject of course is why print a business card then never have any on you when you go out to do business or network?
Ah well - winning a lot more than losing with this subject...