The Haight (pronounced like hate), as SF residents typically call it, is today actually two distinct neighborhoods, the Upper Haight and the Lower Haight.

The Upper Haight is the neighborhood that was once referred to as Haight-Ashbury, and the part of Haight Street that people will assume you're talking about if you say just "the Haight". Though the Upper Haight was once a bastion of peace and love, visitors who come to the neighborhood hoping for a hippie experience will be disappointed. Though there are a few neo-hippies, and it's still a place you can go to score the streets are crowded with tourists and gutterpunks. Though the area is still home to various subcultures (including punk, goth and rockabilly), the corner of Haight and Ashbury has been home to a Gap store for the past ten years or so.

The Upper Haight is a nice place to shop, but I wouldn't want to live there. Some highlights (that is, really unique spots, not just places with cool clothes - you can find tons of those just by walking up and down Haight) of the neighborhood include:
The Red Vic Movie House - a worker-owned repertory theatre that plays cult classics and indie flicks.
The Piedmont Boutique - aka "the drag queen store". This shop makes all of its own clothes and really only has a dozen or so styles, but they're made with such flair using bright fabrics, sequins, and feather boas that one can't help but be dazzled by the selection. Unreasonably expensive, but great fun to browse in nonetheless.
Bound Together - This is a volunteer run anarchist collective bookstore which is worth visiting for its selection of zines alone.
Kidrobot - This J-Pop inspired store sells amazing toys, mostly of the Urban Vinyl line.
Bang-On - A hip screen printing shop that will put one of their great designs (ranging from AC/DC to Buddy Cole ) on shirts that you'd actually want to wear.
La Rosa - A vintage store that's actually vintage, carrying beautiful clothing (mostly) from the 1920's to the 1950's.

The Lower Haight is a newer neighborhood of interest, as it was basically a ghetto until recently. Through the process of gentrification, it has become a much hipper place than the Upper Haight, mostly because it doesn't have the tourists and you get hardcore points for living in a neighborhood that gets more shootings than anywhere else but Hunter's Point. In addition to not having tourists, the Lower Haight is more like a normal neighborhood, where most of the people you see walking around actually live there, which is generally a diverse group of younger alternative types, yuppies, and black folks who were there before it was cool. There aren't as many fun shops in this area, but there sure are a lot of bars and, actually, some really good resaurants.

The border for the Lower and Upper Haight, by the way, is generally believed to be Divisadero.