I have a remote team, but it's because I'm taking on 2 markets that have synergy - the US & Seoul. Both share strong ties. We have one team based in NY, the other team in Seoul.
Advantages: Remote teams can give you access to new markets & you have greater flexibility in hiring.
What it comes down to: strong communication, personal drive, the ability to work alone & trust - this is vital for people working remotely.
Yes. I work at Trello, and the FogCreek trilogy (FC, Trello, and StackOverflow) all hire remote -- and have near 50/50 I believe.