I read a quote of Drew's a while back that stuck with me. Just googled and found it:
"When Dropbox was getting off the ground in 2007, there were hundreds of small storage companies. It was almost a cliche, the way that many people believe mobile photo sharing is a cliche now, he says. “The important thing was, I would keep asking people if they used any one of these hundred options, and they all said no. These are my favorite problems to solve. You can’t focus on what everyone else is doing — it has to be about what’s really broken and what you can do to fix it.”"
He should've said what he did differently - seamless integration (aka virtual drive in Windows) was a selling point, but again, other services also had this.
"When Dropbox was getting off the ground in 2007, there were hundreds of small storage companies. It was almost a cliche, the way that many people believe mobile photo sharing is a cliche now, he says. “The important thing was, I would keep asking people if they used any one of these hundred options, and they all said no. These are my favorite problems to solve. You can’t focus on what everyone else is doing — it has to be about what’s really broken and what you can do to fix it.”"
http://firstround.com/review/How-to-Win-as-a-First-Time-Foun...