I ordered a Nexus 4 8GB.
I live in a 3rd-world country where 3G connections are either expensive or unreliable. Also, we don't have access to all the excellent streaming sites like Spotify or Hulu.
So yes, I need all that space for my music collection :)
I realize I'm also somewhat unusual in this respect.
You'd be surprised. Many games, these days, can take up to 1GB for program and data files. My iPhone 4 with 16GB was so maxed out, it'd often refuse to upgrade more than one app at a time because of insufficient space.