This is a review of the manga, seeing as I haven't seen most of the anime. First the details: Love Hina was penned by Ken Akamatsu, who is also known for the manga 'A. I. Love You', which I haven't actually read, and Negima, which I have read 12 volumes of. Love Hina is 14 volumes long and available in English from Tokyopop.
Plot: Fifteen years ago the then-four-years-old Urashima Keitaro made a promise with a girl that they would meet up again at Tokyo University. Unfortunately he hasn't seen the girl since and he has since been rejected from the University two years running. After he decides to apply for a third time he is kicked out of his parents house, and goes to live in the inn owned by his elderly grandmother. He arrives, only to find that the inn has been converted into a dormintory for girls run by his aunt. Of course he doesn't find this out until the usual ecchi hijinks have ensued causing a huge amount of misunderstanding. After a few arguments he is allowed to stay at the dorm when his grandmother passes the title deed to the building to him by fax.
Review: Firstly, I want to go over what I thought of the plot. From the summary I've given you it would seem to be just another harem series. This is not the case. The narrative skillfully weaves several plotlines including Keitaro's desire to get into Tokyo University, his growing relationship with one of the girls in the dorm, and subplots involving most characters. The relationship that Keitaro develops with one of the girls throughout the series is actually rather well-founded. Most harem series tries to confuse you as to which girl the main character will end up with, resulting in a relationship out of nowhere towards the end. Akamatsu takes a different route. By the end of the first volume we can tell exactly which girl Keitaro will eventually get together with, which leaves Akamatsu the rest of the series to develop a believable relationship between them. Many people are put off by the traditional humourous violence that is inherent in the genre, but you have to look past it.
Art: I once read that Akamatsu-sensei used to draw hentai, and the skill with which he can draw the human form makes me inclined to believe it. Because most of the series is set in and around Hinata House (the girls dorm), backgrounds tend to be used again and again.
Characters: The main characters, Keitaro and Narusegawa Naru, are very well developed, although I find Keitaro a little annoying. The other characters start as very simple archetypes, such as the crazy foreigner (Koalla Su), the shy one with a juvenile crush (Maehara Shinobu), the reserved swordswoman who isn't sure how to deal with the opposite gender (Aoyama Motoko), and the money-loving gambling alcoholic prankster (Mitsune 'Kitsune' Konno). All of them are traditional archetypes for the genre (although the swordswoman isn't always a swordswoman, just somewhat reserved!), but the subplots which Akamatsu integrates into the manga mean that they rise above these simple stereotypes. The only exception to this is Kitsune, who is still the same character near the end as the beginning. To his credit, Akamatsu mentions this in the notes included at the end of one of the volumes, but that doens't make up for not giving her more to do. She is most often used to further the plot, often by accidentally revealing information. Again, to Akamatsu's credit, he has a character much like her in Negima who does get the screentime she so richly deserves.
Overall: This was one of my first manga series, so naturally I look back on it with some fondness. In fact, writing this review had made me more than a little nostalgic about it, so I will probably read it again when I get home from University. If, in a couple of weeks, you have a post here rubbishing it, that's why. However, until then, I have very few bad things to say about it. It takes the usual harem genre and completely subverts it and shows that it can be done really well.
8/10: Excellent series that everyone should read.