Emo is a sort of commercialized angst, or at least a fashion movement.
Emo does not equal "emotional", I think it is music that is almost fake. Bands that aren't only selling their music, but selling their clothes or hairstyles. If a musician has deep lyrics, and I really do mean DEEP lyrics, it's not emo then. But if the lyrics are about some random love story a band made up that's like any other song, then yes I would consider it emo. Because they're probably trying SO hard to be deep about their lyrics, but it's just the same as everything else. It's fake.
For example, Secondhand Serenade, Nevershoutnever, or any band/artist like that I would consider emo, because the music seems fake to me. The lyrics suck and is commercialized angst.
Here's bands that are more about their clothes or hairstyles that people would call them emo: Fall out boy, Metro Station, you know...bands like that where the clothes fit the kind of "emo" look. Skinny jeans, black hair (usually parted to the side) and other cutesy-very tight looking clothes.
Now I am aware that emo used to mean music that was emotional/punkish. In the 90's I believe with bands called Rites or Spring.
So, bands that are considered emo, but shouldn't be.
BRIGHT EYES! That's like, the best fucking band in the world but people call it emo because it's emotional. Yes, it's emotional, BUT if you think about what emo means now (commercialized angst, style of clothing) it's nothing close to it. I guess any indie sounding band is consindered emo. Like Death Cab For Cutie. Nope nope nope. NOT EMO.
Once the "want to become emo" read through all the websites and looked up bands that websites considered emo, he gave himself a total make-over. First, he needed to get the right emo wear, so he bought some skinny jeans and dyed his hair black, and painted his nails red and black. Now that he has been partly sucked into this emo style, he needed to learn the right music to listen to. The websites told him to listen to My Chemical Romance, Fall Out Boy, Taking Back Sunday and any band that screams that whole time. The emo kid didn't really understand what made all the bands emo, but he did it anyways, because that is what the websites and shows on MTV have been telling him.
But then, he read that he had to cut himself and believe himself to be depressed. So, he started to fake being depressed, until he believed himself so well, that he cut too deep and died.