http://pc.ign.com/articles/116/1169063p1.html
"Valve --best known for developing the critically acclaimed Half-Life series --revealed via a press release that Half-Life will not make an appearance at E3 2011. In fact, no Valve games will be there. According to Doug Lombardi, Valve's VP of Marketing, media outlets needn't make any E3 appointments because "[Valve is] not showing any titles at this year's show. So no appointment is needed."
This is getting old.