I really don't know any more details than I've seen just now on Amazon — but it looks like the Mass Effect 2 Collector's Edition comes with a limited-edition copy of Mass Effect: Redemption #1. That's the first issue of the new series I scripted based on game designer Mac Walters' plot, with art by Omar Francia. There are XBox and PC versions, according to the site.
I don't have any details about the comic book included — including whether it's the same one we're doing or how it differs — but I'll look into it after the holidays.
Sounds like a nice bonus — there's other things in the package, like a bonus DVD. Thanks to Nate Melby for the heads-up!
Update: IO9 has a variant cover here — not sure if it is the one for the special edition, but it's nifty-keen.