Having thoroughly enjoyed the first volume a few years back when it was translated by Aku-tenshi, I had high hopes for this show. And boy, not only did it meet expectations, but it far exceeded it.
Spoiler for slight spoiler for eps 1, though if you hadn't seen the show you probably won't understand me anyway:
Not only was the show very amusing, but the addition of the 'arrow' in the beginning made it quite interesting indeed. The short mystery as to why they wanted your attention on the arrow was enjoyable in this persons POV.
Another thing they added that wasn't in the manga and did right was the addition of the light bulbs. Like the arrow, it serves to give a little bit of mystery as to why it was added, with it's full signifigance only revealed till the very end. Unlike the manga, the show, using the light bulbs, actually highlited the exact moments when the host club discovered Haru's true identity, and thus gives the ending scene much more of a punch.
While it is only the first episode, it's refreshing to see a show in which it actually IMPROVES the original source, rather than blatantly copying it 100% (which fails the vast majority of the time).
In any case, this is my #2 must watch anime this season so far. Anyone looking for a romance anime (though very light the romance in this show might be) should give this show a shot, since the alternatives to this season are few, and good ones even fewer.
(#1 oddly enough goes to Zegapain, which is quite damn weird since 1] I'm a shoujo/bi-shoujo/romance fan and 2] I generally dislike mecha shows)