I am not that big into sketch cards as the medium is just too small for me. I have been collecting original art for a number of years and original comic art is one of my favorite genre's. Going from 11 x 17 drawings to card sized sketches just doesn't do much for me at all. If Wacky Packages starting making sketch cards for their postcard series that were full sized postcards....well, I would be all over those!!
I do have to admit that the whole ACEO card craze that sketch cards have kicked off is pretty amazing. For those unaware, ACEO stands for Art Cards, Originals and Editions. Basically the sketch card craze has basically spilled over and you now have artists from all over the world, from lots of different fields, making their own sketch cards. Just do an ACEO card search on eBay and you will understand very quickly just how big it has gotten. Its been really interesting watching the whole thing unfold. Again, the size if my biggest issue. I am not complaining tho as its made buying unopened boxes FAR cheaper without the sketchcard. I just purchased 10 boxes of Old School Series 4 for just 10 bucks a pop. I doubt that would have been possible if Sketchcard's weren't involved.