The overwhelming majority of artists I listen to these days would be broadly classified by the general public as "indie." Cut Copy, The Hold Steady, Fleet Foxes, Wolf Parade, The Decemberists, Antony & The Johnsons, TV on the Radio, Iron & Wine, so on and so forth. A lot of this is the result of the Internet -- i.e., I can freely test out the music of whomever I want whenever I want to see whether I want more. There are tons of bands I listen to these days which I never would have gotten into if not for the availability of downloading and YouTube samples. As Yglesias said awhile back -- whatever one may think of the dubious legality (read: illegality) of downloading music, there has never been a better time to be a music fan.
However, problems (not really problems, but, you know, "problems") arise because while many of the aforementioned arists, and others, are huge huge huge in indie circles, most of them lack name recognition with the general public. So when someone asks what I'm listening to these days, I might say "Jaguar Love, MGMT, and The National," and I am rewarded with a "What are they?" Now my first inclination is to say "indie rock." But this isn't really right, because these bands are very dissimilar, and the broad brush of "indie rock" does a complete and utter disservice to the specifics of their actual sounds. This issue is somewhat unique to modern times amidst a market flooded with artists; in the 1970s, if you had band or artist you were digging, nobody would have to ask who he was or what they sounded like, because it would already be plastered all over the radio. Not the case today.
So back to the issue at hand. Let's take the following artists: Wolf Parade, Animal Collective, TV On The Radio, and Sufjan Stevens.
Wolf Parade: Kinda synth-centric, keyboard-heavy (Check "The Grey Estates"), very catchy band with lots of purposely obscure/laughworthy lyrics. One of the standard bearers of "indie rock" at the moment in that they have a huge following but aren't quite as big as The Decemberists or anything.
Animal Collective: Best compared with the SMILE-era Beach Boys, but that doesn't really mean anything. Purposely use nonstandard sounds and lots of electronics to create one big faux-modern Wall of Sound thing. One of the least accessible indie bands there is, but also one of the most highly acclaimed. Requires quite a few listens to get into them.
TV on the Radio: A few black guys who... honestly, how am I supposed to describe them? A band that does this and this? What's the connection? "Sometimes hard-and-fast mosh-pit-worthy rock, sometimes a black man's Radiohead"?
Sufjan Stevens: Very happy and pleasant on the ears. Nothing inaccessible about him, but very complex nonetheless. Terrific songwriting -- Iron & Wine with an orchestra and better studio equipment. The question remains: how do I categorize him into a simple genre?