Spotify because I can find basically any song I want
And I use Itunes so save my own personal songs for my ipod.

iTunes, because I like it more and I have an iPhone.

Itunes on Windows because I own an iPod
Clementine on Ubuntu

Spotify.

iTunes and my iPhone remain superior to any other type of music player.

iTunes, I tried Spotify but iTunes feels just more....comfortable

Windows Media Player lol

(And Spotify)

iTunes/Spotify

iTunes

iTunes. I don't think I could get used to Spotify, not owning my own music

Windows Media Player. I've tried Zune, iTunes, Winamp but I keep coming back to WMP. It suits me best.

iTunes. It's the only software that allows me to organize my stuff the way I like and has a nice interface.
They need to bring coverflow back, though. Or at least adjustable size for the covers.

A combination of ITunes/Spotify.

Clementine, nice and simple

But it's annoying cause I keep having to delete duplicate scrobbles on my last.fm profile

+1

Spotify and iTunes both. I use Spotify to listen to music (along with the Local Files playlist to play downloaded songs) but I use iTunes to change album data and sync music to my iPhone. I don't use Local Files on my iPhone because it's too much work to sync so I just use the Music app, but I still use Spotify for streaming.

Spotify.