E3 2009 seems to be bringing back at least a few PC hardware companies. Intel and Nvidia are listed as exhibiting on the show floor and Dell's Gaming unit (that means Alienware) is also listed as showing up at the show. But there's evidence that Dell-Alienware are prepping a major E3 announcement.
Alienware recently sent word about a new web site called www.allpowerful.com with a Flash-driven animation set up, alien letters and countdown clock that will run out on June 2. That just happens to be the first official day for E3 2009. You can sign up to get a email notice about whatever it is they are planning to reveal. Until then, watch and wait.