Superman and Batman: Pretty decent, I'm a fan of Loeb's work, so that helps. Hardly ever seriously dissapoints.

Brave and the bold: Superman & Batman "light" with a bigger cast. Storylines go from good to decent.
Countdown series: Keep reading if you've been reading so far, if you haven't you really haven't missed anything.
Amazons attack: Pretty good, but somewhat connected to 52 and countdown.
Flash-fastest man alive: I enjoyed the series, and since it's a short one and has one of the best titles for a series considering how it ends, I'd recommend picking it up.
Nightwing: I would say one of the best Bat-related books at the moment. It's not saying much (although all Bat-books are decent or better), but the story somehow gets better and better. worth checking out atleast.
Batman Confidential: Like most of the bat-books, not bad, but nothing spectacular. If you like Bats, then check out atleast.