The conference is not about using credit cards on the internet, but rather a slew of topics connecting computer science and economics, lots of auctions and networks for instance. I am general chair this year, a bit more challenging than the six years I spent in the same position at the Complexity conference because of having to integrate the different cultures of CS theory, AI and economics.
But EC is not the only game going on right now. ICALP, the major European theory conference is happening as we speak in Iceland while in Finland we have COLT, the learning theory coference starting Thursday. The sun won't set on ICALP or COLT this year.
Let's not also forget the IEEE International Symposium on Information Theory in Toronto so nicely described by Mitzenmacher.
Unfortunately conflicts like these require difficult choices. I (and many others) have attended and had papers in ICALP, COLT and EC in the past. Why do we have these conflicts? These conferences need to be planned out years in advance with a number of various date constraints making coordination very difficult and early to mid July makes for good conference dates as a post-classes, pre-vacation time in many countries. As CS expands and adds more conferences to cover the increasing number of papers we produce, this problem will only get worse in the future.