Sorry to be both predictable and sort of up-to-date in my tastes for a moment (two things that go against my mission statement), but I should report that, yes, "Veronica Mars" is as good as everyone says.
It was a relief to disover that the creator, Rob Thomas, understands how to make an audience take his characters seriously without taking the premise too seriously. There are a lot of shows with ridiculous premises -- especially the ones that involve kids or college students doing dangerous things -- and there are two "extreme" ways of dealing with a ridiculous premise. One is to go the "Batman" route and just play the whole thing for laughs. The other is to simply do a show with no humor, where everybody acts like this premise is the most important and incredibly realistic thing in the whole wide world. This produces my least favorite type of show: the ridiculous show that's too square to realize it's ridiculous. "Alias" is like that, and I can't stand the humorless pomposity of "Alias." "Knight Rider" was like that, and I like that a little better than "Alias," but not much.
Anyway, "Veronica Mars" has a basically insane premise: the lead character is a teenage master detective who can solve cases for her classmates and for her struggling P.I. (and ex-sheriff) father. The premise is a distaff "Encyclopedia Brown," but set in a town where everybody has some kind of dark secret and tough talk and double crosses run rampant. It's like a film noir in color and set in the 21st century and starring a kid who fills the role of the world-weary private eye. And every episode is filled with things that just wouldn't, and don't, happen.
Luckily, the tone is just right: there's a sense of humor about the premise, without being campy or coy about it. Any particularly nutty plot development is handled with at least some hint of humor that shows that the writers are not trying to make the premise out to be more serious than it is: the humorous touch can be as little as a wisecrack from Veronica or as obvious as her bringing along a dog named "Backup" on a detective job for her father (who told her to "take Backup" if she goes out on the job), but it's there and it's enough to deflect any suspicion that it's in "Alias"-style denial about the silliness of its concept.
It's not laugh-out-loud funny like "Buffy the Vampire Slayer" was, but it's based on the same underlying idea, which is to play fair with the audience. They tacitly admit that the premise is silly, and we (and by "we" I mean me) are more likely to take seriously the stuff that is not silly: the characters and their emotional conflicts. (It's a bit like the technique used in a classic film noir like Out of the Past, where the more absurd elements of the plot are handled with a slight touch of humor, but the big moments of character development are handled with the dead seriousness they deserve.) It also allows them to get away with some fairly standard mystery stories, because we understand that what's important in the episode is not how the mystery gets solved but what emotional conflicts arise while the story is in progress. Whereas with something like "Alias," I can't take the characters seriously because the show seems to expect me to take everything seriously, and makes no apparent distinction between what is silly and what isn't.
"Veronica Mars" also takes advantage of something that most "teen" shows ignore: the extent to which technology has made it possible for kids to complicate their lives as much as adults. With internet access, cell phones and other electronic miracles, the kids on the show sort of have instant independence, and can get involved in plots that previously only made sense with adults. The second episode takes a very standard story: the poor sap who lives beyond his means to please a worthless, spoiled woman, and winds up stealing to give her the life to which she has been accustomed. It's all there, but normally that story is done with adults; here it's done with kids, and you realize that with access to credit cards, cell phone communication, and other things that These Kids Today take for granted, this old plot can quite plausibly be acted out by kids.
And that fits in with a theme of the show, that the things kids have to deal with -- emotional crises, issues of class and status, financial burdens -- sort of turn them old and cynical before their time; the lead character has, as the show begins, been turned into a hard-boiled cynical adult, while her father seems like more of an innocent. The theme that kids are now forced to live and suffer like grown-ups is in equal parts funny and truthful, which is what you want a show like this to be: funny, but emotionally true.
Rob Thomas's previous show, "Cupid", was a one-season show that got great reviews, though its production was, apparently, troubled (two producers quit over what they described as "Creative differences with its pathological star"). It'll probably get a DVD release one of these days.