So far, I had only commented on cards from piu58, rst and MattKing. But there's more! I've also received:

Mike Wilde's threesome, always a treat! My favourite is Birds at the Blue Water Bridge, a lovely action shot. When I get that close to birds, they all fly away before I can even get the camera ready. How did you do it? Anyway, three great shots, and always a pleasure to see what is still possible with old mystery paper.
anikin's Colors and Forms, now that is something. Sharpness, detail, and obviously lots of colours. Great to look at in these dark grey days near the end of the year. Happy.
ozphoto, Berlin. We also visited Berlin earlier this year, and I share your sentiments. A lovely photo, the Fernsehturm reflected in an office(?) building. Great colours.
Jim17x, Speedy. Well, that gives me an idea for the next 15 to 20 postcard exchanges Except that your Speedy makes for a very nice subject, whereas my camera collection is dull at best. Nice low-key shot and print.
ChristopherCoy, music in the street. Good example of street photography; not too easy with the dark background. I would like to see it printed with just a bit more "punch", a bit more blacks.
drpsilver, happiness is... Only too true, a nice still, and a clear message. Nicely printed.

That's it so far. And... my cards went in the mail yesterday. I received my own card today, which is proof that the mail service has emptied the mailbox and processed the mail. I hope my cards find their way around the globe.