Excellent visuals which at times make it seem like you are watching a big budget movie production.
Story wise the series revolves around the very interesting Prohibition Era and everything that surrounds it. With such a large cast at first it may be somewhat confusing to follow some stories without getting confused, but this being the first episode, it is to be expected and no doubt as the weeks pass, we will familiarise ourselves with the characters represented by a very good cast.
....and there's GORE. watching someone get obliterated by a shotgun to the face ..AWESOME!!!

It's also apparently got picked up for a second season already

http://www.hbo.com/boardwalk-empire/index.html