Back Issue Ben: Captain America #1 is the easy answer. I knew something big had happened, but I was able to avoid the specifics until I had a chance to read it. The Rebirth issue of Detective Comics was a nice surprise. Batman treating Batwoman like a respected colleague (hell, him treating anyone well is a nice surprise) and her revealing she always knew who he was. That and the team they're putting together, all made for a pleasant surprise.
Migs Acabado: I had to go with The Wicked + The Divine. When I started reading the first volume, I found it very confusing and then as the story progressed, it became more interesting and exciting. The biggest surprise for me is during the end of the second volume. I never thought that was gonna happen. You can't do that to your main character! You just released two volumes. It is too soon!
Jeff White: Daredevil #5 (vol 2). The death of Karen Page really caught me off guard. They didn't even tease in the solicits that there would be a major death (which is a bit surprising in itself) The Marvel Knights team had everyone checking this book out at the time and threw a shocker in it right before the end.
LaMar Forte: It may not be the last one, but it's the first one I can think of: Old Man Logan was a lot better than I expected it to be. I'm not the biggest fan of Wolverine, but I'm not averse to him and especially so when he has both a great supporting cast and interesting things to get into. That fight with "Bullseye" was perfectly paced and probably the extreme case of what Wolverine is capable of as a force of nature, and the art and story pacing totally sells it. End to end burner-no lies told, B.
Duy: I'm on Book 10 of Vagabond at this point, and one of the reasons I'm reading it, other than it being captivating and pretty, is that it's so economical and is paced so fast. With work taking time away from reading comics, I'd like to go to things that read fast, and Vagabond does that. One of the ways it goes fast is due to all the silent sequences. Mostly, these are fight scenes. In the most recent installment I read, two childhood friends and would-be lovers are reunited after basically being apart for the whole series thus far. The reunion is silent, and it lasts for several pages, and it's pretty freaking powerful, and if I had tear ducts, I might have cried.
Benj Bartolome: The Fade Out was great for me, a surprise because I don't even remember which Criminal book I read long ago (in short, unremarkable to me). Also found three Dylan Dog digests in a sale bin, and I wish I could find more. It's got a solid mix of straight-faced wit and weird fantastic sexy. I'm not surprised though, that the movie adaptation with Brandon Routh was said to be awful. I imagine that kind of tone would be difficult to emulate, especially when the source is from a different culture. Like Judge Dredd is supposedly a difficult grasp for not Euro people (talking out of my ass).
Matt: I expected Darkwing Duck to be so terrible. It wasn't. It hit the right notes of the TV show, but also added nice touches and allusions to comics. I would go back to reading some more of the Boom! series if I get around to it.
Travis Hedge Coke: Three-way tie: Constantine, for having a new issue at all, and one with a shocking twist that made a lot of sense. The Last Crusade, because it's the only time Catwoman's been more than a brutalized victim in a Frank Miller comic other than Year One, and she's the voice of reason! And, lastly, I'm still shocked, delighted, and a little dizzy over Patsy Walker: AKA Hellcat referencing Nancy Brown after Marvel's kept her out of everything Patsy for the last fifty years.
Edrick Tan: Sleeper. I was lucky enough to find the first six issues for super cheap, otherwise i wouldn't have considered this title. It got my attention because of the glowing reviews from various comic sites/magazines, and the premise sounded interesting enough. Still, I did not expect at all that i would love it as much as I do. It was probably my first "superhero-crime" comic book and it just totally blew me away. Made me a Brubaker fan ever since. It's probably still my favorite Brubaker-Phillips book. TAO is one of the most formidable villains in comics and among my favorite Alan Moore creations.