From today's Gamespy newsletter:

Will it suck in new players? Who will pay?Magic: The Gathering Online Events - Prophet
Wizards of the Coast will be showcasing Magic: The Gathering Online, the (obviously) online, digital version of their ultra popular roleplaying-flavored collectible trading card game for the PC. They'll be showcasing what this game has to offer at their E3Expo booth (#4005, Petree Hall) with a variety of activities including a head-to-head Magic Online competition between Magic: The Gathering Creator Richard Garfield and Magic Pro Tour Player Chris Benafel, along with game demos, interviews and other interesting and fun stuff.