Personally I find the series quite awesome. It doesn't have flamboyant plot twists - only one death shown in 150 chapters is really an achievement for any shoujo manga - but the characters develop and grow, and that's what captured my soul.
For one thing, they grow physically: Haruto and friends start out just starting high school, and in recent chapters have been enjoying university life. Granted that the manga could do more in actually showing school life for once, but at least it's still realistic: they spend most of their time figuring out the relationships that they end up in some second-tier university (we know because Eba's sister Rin wants it as the second choice, and Eba presumably is already in a top-tier university). But aside from progression in life, they also physically get bigger, and there is attention to detail. Anyone who's watched Pokemon from my time knows that Ash has been 10 years old for about ten years now (oddly enough, he's somehow gotten slightly taller).
Finally, and most importantly, the characters develop. Haruto, by virtue of his kindliness, becomes more mature and serious about his relationships - a far cry from crushing on Nanami and then asking her out after two or three conversations in their whole lives. Perhaps the clearest contrast is when Eba is used as a foil: the very first chapter shows a 16 year old Haruto stumbling down the stairs protesting the new family member's presence, and recently he's moved into his own apartment in Tokyo, the down-payment handled by Eba and Haruto together. Character growth is, of course, observed in all the other characters throughout as well - Takashi and Kiyomi both get over their respective hurdles, for example, and Rin becomes less overtly bitchy. So life goes on.
Throughout the maturing of our friends, we see complex themes interwoven into the storyline: love, loyalty, trust, belonging, family and whether blood ties are all that defines one (Eba and siblings v. Eba and Haruto). Life lessons are learnt through the experiences and choices that are made throughout: Haruto moves to Tokyo against his parents' and friends' wishes, Eba breaks up with Haruto for Kyousuke who later dies, Haruto gets over Eba with Asuka, and Haruto dumps Asuka for Eba. Most of these choices are made by Haruto, the main character and perspective we see the story through, but we do get the back stories of our other friends.
What's significant is how difficult the choices are, and how it's no mean feat making them all: Haruto, for example, throws away his chance at conquering his long-held crush on Nanami to make sure Eba gets home safely. Unlike other shoujo manga where a filthy-rich prince comes in with an army of secret police to save the day, Haruto has to go by himself to ensure Eba's safety (gets lost while looking for her), punches her brother to get his point across and goes home with an enlightened understanding of why Eba came to Hiroshima. There's no easy way out, as Rin tells Haruto: "Aren't you being a little selfish now, not wanting to hurt either of them?" Indeed, Haruto breaks up with Asuka against the will of all his friends, and invites a backlash - Kiyomi warns Haruto poignantly, "Nobody will ever obtain true happiness if they have to hurt someone else to gain it." (Nanami pretty much tells Eba the same thing), but Shiori, an outsider to Haruto's circle, tells Haruto: "For what it's worth, I don't think what you did was wrong." And that's it: sometimes we just have to believe in our own decisions, and walk forward. The process of making tough choices in Kimi no Iru Machi, without any knowledge of what the future may bring, reflects the harsh truths in reality via beautiful, complex interwoven illustrations, and forces both character and reader to grow up and abandon the innocence of yesteryear.
The similarities to life don't end at the decision making stage - the characters are very much people you might know yourself, giving greater credence to the title "A Town Where You Live", precisely because you feel like you might have lived there yourself. The protagonists and antagonists reflect reality: shoujo manga commonly have a girl and a boy fated to be together, and rivals appear with a million schemes. In Kimi no Iru Machi, there are no clear-cut heroes. We are always inclined to take the side of the one narrating, but in Haruto's case, he makes so many blunders when it comes to his love life that - despite his natural kind self - we do sometimes get rather pissed off with him. (Isn't it obvious that when you're courting a girl, you do not abandon her time and time again for another girl, and then lie to her about it?) The relationships aren't cast in stone right from the start - no one expected Eba to break up with Haruto, no one expected them to move on, and in recent chapters, probably no one expected Haruto to be hardhearted and dump Asuka for Eba. It could have easily swung any way. And there isn't really anyone at fault, much like life - it simply is. No one can control who they truly feel for, and what they truly feel. The closest we get to an enemy is Rin (she certainly seems like the typical manipulative bitch initially when Eba returns to Tokyo), but later on we revise our opinion - the most she does is cause annoyance by interfering all the time, but she doesn't really have an agenda - she isn't out to make Haruto her own property.
The single criticism weighing on my mind right now is that there are too many girls. Normally, I am all for fanservice (mm), but when as a guy I start getting turned off by the quantity of girls, I think there's a problem. Discounting the childhood friend who kisses him (Akari), the girl who drags him to a love hotel (Shiori), and the girl who mistakenly thinks Haruto likes her and ends up stalking him (Mina), Haruto has had no less than five girls falling in love with him - current girlfriend (Yuzuki Eba), initial crush (Nanami), ex-girlfriend (Asuka), ex-classmate (Kiyone) and current neighbour (Hoshina). This is also omitting his hot sister who lived with him in Tokyo (Aoi), Eba's sister (Rin) and his best friend's new crush (Kiyomi). There are two guys still in the manga: Haruto and his best friend Takashi, who's normally forgotten - Kazuma, Eba's ex, is now dead. The current neighbour's probably going to constitute the next arc. As much as I agree that nothing is certain in this world, the Law of Large Numbers suggests that the more times an experiment is conducted, the more the result tends towards the mean. In this case, I think it's high time for Eba to get some of the action if nothing else - clearly, five-to-one is no healthy relationship ratio. It's getting slightly tiring - and annoying - that Haruto, who has been touted as slightly useless and unattractive from the beginning (he joins the cooking club and loses to girls in athletics) is getting so much action from so many girls. In the end, having 9 main, developed female characters onto 2 male ones should feel imbalanced to even the guys - let alone the girls. It's nearly as bad as Mahou Sensei Negima - and that's saying something!
Ultimately, though, it remains a must-read for anyone who desires a tale as close to real life as possible - that is, without the many house renovations forcing a man and a girl to live together, or multiple gangs threatening the lives of a girl and a mysterious black-belt and top in nation martial artist saving the day. Truly, the manga captures the ideal pastoral life with its motif of the bicycle Haruto and Eba used to cycle on to school every day.