For as long as I can remember, my favorite part of the movie-going experience has been watching the previews. But, in the last few years, my response to most of the previews can be summed up in one sentence: “Who thought it would be a good idea to green light this?”

You can’t completely blame the movie studios; they just make what people want to see and they gauge this by seeing what makes money. If “Meet the Spartans” was No. 1 at the box office, who are we to complain when “Meet the Spartans 2: Longer and More Asinine” comes out in a few months?

That’s why I’m so happy when a movie like “Juno,” a critical darling and box office success, comes out. It’s that rare blend: Smart and funny, but also appealing to a mainstream audience. Every time a movie like this arrives in theaters, such as last year’s “Little Miss Sunshine,” people who are about to give up on American cinema for good get a little glimmer of hope, at least until the next Dane Cook movie comes out.

“Juno,” directed by Jason Reitman (of “Thank You For Smoking” fame) and written by Diablo Cody, a former stripper, is the story of a teenage girl (the title character, played by Ellen Page). After becoming pregnant during her first time having sex, she decides to give the baby up for adoption to a couple she finds in a classified ad (played by Jennifer Garner and Jason Bateman of “Arrested Development”). She forms an unlikely friendship with Jason Bateman’s character, a wannabe rock star who is not quite ready to grow up, but becomes disillusioned as the marriage between him and his uptight-but-loving wife begins to unravel. Despite her fear that relationships will never last, Juno is able to find happiness in her own relationships with her best friend, her dad and stepmother, and her baby’s daddy Paulie Bleeker (Michael Cera, who can play endearingly awkward like no one else in Hollywood).

There is little not to like about this movie. In fact, it’s so close to being flawless that it might even have been annoying — the dialogue a little too witty, the music a little too precious — but it’s too irresistible to be irritating. Despite how cool “Juno” is, both the character and the movie has such a big heart that it’s hard not to fall in love with. By the end of the movie, I wasn’t sure if I wanted to be Juno, be her friend or date her; but it’s definitely one of those. “Juno” is not just another cute indie movie, it’s one of the best movies of the year. Just ask the Academy. Hopefully, the attention this movie is getting will send a message to the powers that be in the filmmaking business that we’d like more of the same.