Whoops! A listing for some Mass Effect 3 downloadable content made an accidental appearance on the Xbox Live Marketplace. It's since been pulled by the powers that be. Titled "From Ashes," this add-on will cost 800 Microsoft Points when it releases officially.
Thanks to the summary, we have a good idea of what this content is. In it, we'll "unearth lost secrets from the past" and recruit a new squad member, presumably the same one previously depicted in concept art. This is far into spoiler territory for many of you, so that's why you're looking at Total Recall.
It's believed that "From Ashes" might be available for free with new copies of the game, similar to Zaeed in Mass Effect 2, but nothing has been confirmed. If you have the same spoilers-be-damned attitude as me, check the link to IGN to see the mystery character.