Source code gibberish! These files have a few sections of dialogue between Shepard and Liara speaking about going after the Shadowbroker, and after going after him. So, if this dialogue is to believed, and isn't just remnants of a mission that was removed last minute, the next DLC may be a significant addition to the Mass Effect mythos, AND giving fanboys what they wanted from the start: the ability to have Liara in your party, even if it is just for a mission.
For those of you who need context to... contextualize things, here is a handy video some pleasant chap put together that inserts that found dialogue into scenes of the game. Careful, definitely potential spoilers!
Some of theorized that BioWare might be saving this full on expansion, ala Dragon Age: Awakening. Though I have a feeling this is just well wishing on their parts. All I hope for is a mission that actually adds to the ME story and lasts longer than an episode of Lost (sorry Stolen Memory, I still love you), and I would be pleased.
What's your guys' take on this?