Bravo, Kralik. Awesome post.
PS: I'm still interested in seeing a "virtual store" for singles on GCCG, if it's possible. Meaning: no one is gonna buy commons (ok, they will, but not nearly enough in proportion) enough for people to get rid of their 90 copies of a single one. I was thinking that maybe GCCG could have (for those interested in collecting/playing without proxies) an option to sell a card to the in-game store. It would simply vanish (so it wouldn't "compete" with players for selling cards), and it would pay a BUCKETLOAD less, but it'd be STILL a way to get rid of excess unwanted cards that pile up after a while. So, for instance, a full playset of a common could be sold for 0.01. Uncommons could be sold in playsets (for a little more) or singles, but with reduced prices. For rares, it could be simpler, just making the in-game store pay, like, half what the cheapest price available is or set amount, no matter which rare (and a low one).
PPS: I don't want to start a topic (and a ruckus) out of this, but if you feel it's worth it, feel free to clip the post and move it.