Looks like they are releasing the previews via flash this year - and not pdf.
Personally, I can't stand reading comics this way.
Writer: Geoff Johns
Artist: Ivan Reis, Andy Kubert
This is the perfect jumping-on point for new readers who can't wait to see the Green Lantern major motion picture from Warner Bros.! Discover how and why Hal received the power ring that changed his life forever with this reprinting of Green Lantern #30, a pivotal chapter of the Green Lantern: Secret Origin graphic novel by Geoff Johns and Ivan Reis. Plus: No comic fan can afford to miss this exclusive first sneak peek of Flashpoint, DC's blockbuster event of 2011, by the all-star team of Geoff Johns and Andy Kubert!
Available: May 7th, 2011