Wildly inaccurate prediction for the end of this season:
(SPOILER)Deb overhears Quinn and Mr. Bad Cop discussing Lumen and Dexter's nightly activities and confronts Quinn about it, who denies everything and then comes clean. Deb ends up supporting Dexter (even going so far as to help him track down the rest of Crash Override's Rape Crew Fantastic) and Quinn tries to use it as leverage but fails miserably (resulting in either compliance with Dexter or violent and amazing death). Oh and Lumen/Deb kills Mr. Bad Cop to protect Dexter's identity. I'm going more with Lumen on this one though, because Deb cries too much to be a serial killer, though last night's episode showed that she can be emotionally withdrawn enough to help Dexter plot bad guy deaths.
LaGuerta and Batista get divorced because she is a and Angel goes back to being an amazing character or taking over LaGuerta's job after she gets fired for being an insufferable .
Masuka quits his job and starts producing, directing, and starring in a series of wildly popular forensic-themed porn movies.