I just watched the first episode and it's pretty fucking cool. It's based on the DC comics character Green Arrow and the first episode left me wanting to immediately watch the next one and blow off the things I was meant to be doing. If the show continues to emulate how the first episode drew me in then I think it'll be a winner.
I compare this show a lot to Smallville (both CW, both super heroes). They took everything I disliked about Smallville and fixed it. No campiness, little bit darker, faster plot, etc. It's not award winning TV by any means, but highly entertaining. If you liked Smallville, you'll defiantly like it.
I just finished this show. It's pretty decent, for CW. The actors are not...great, the men are better at flexing, abs, and gymnastics than a believable presence, but the twists and turns are pretty fun. I don't know much about the comics, but this combines a lot of fun elements from some popular shows, so it's worth a watch. Here's hoping for season 2.