After first two or three episodes, I've got an impression of anime thematically somewhere between "Suzumiya Haruhi no Yuuutsu" and "xxxHOLIC", but made in style of "Sayonara Zetsubou Sensei". These anime are few of my favorites, although that doesn't guarantee that mix of them would be successful. In this case it was!!
We follow few days in life of Araragi Koyomi, who is a normal high-school boy (not completely normal, but he acts as one, anyway), who helps various girls to overcame their supernatural problems. This covers similarities to "Haruhi" and "xxxHOLIC". For likeness to "Sayonara...", anime is composed mostly of dialogs and monologues, with sudden cuts in scenes; design of characters is very similar between these two; and voice-actor is same for male-leads of both anime.
Plot and cases themselves are nothing amazing (girl got obsessed by evil spirits or cursed...); one thing that attracted me to this anime (same as to "Haruhi") is romance aspect of story. Of course, every girl protagonist has (at least it's suggested she has) romantic tendencies to main character (it would be too simple to call it a crush). And of course, we know that he likes only one girl (I still haven't watched longer version of "Haruhi", so I don't know how this was settled there, but here is different). All this sounds very naive and simplistic, but I think that in one of older post I already noted that I'm a sucker for romance.
Best episode for me so far was episode 12, where Araragi has a date with his girlfriend, Senjougahara (this is not a spoiler since there is not much of plot). Most of the episode consists of witty and provocative dialog between the two, with a love confession at the end.
From technical side, I already mentioned that series is made in style of "Sayonara Zetsubou Sensei". I admired it much: nice, bright colors, many static images, unique characters (who often wear different clothes)... Sounds are also nice (I notice only bad SFX, or exceptionally good ones), music too; there are five opening and one ending song.
In general, I would recommend it to people who liked "Haruhi...", but also like a bit more adult anime. As I mentioned, dialogs are strongest part of this series (I had to rewind it few times to get it all right), so beware. I found it on Wikipedia that it is based on light novels, so I hope for more episodes in future.
Next, I will do a re-read of "The Black Jewels Trilogy" by Anne Bishop. I have an omnibus edition that I've read year or two ago and find it good. It will be interesting will I change my opinion after I read it again. Next post will probably be after first part of trilogy.