Now in my opinion, this seems pretty LEGEN... wait for it... DARY!
http://us.battle.net/d3/en/blog/6968517/
Here’s how it works:
After you hit level 60, any further experience you earn from killing monsters will begin to count toward Paragon levels
There are 100 Paragon levels
Every Paragon level will reward you with:
Core stats such as Strength, Dexterity, Intelligence, and Vitality in amounts similar to what you’d gain from a normal level
3% Magic Find and 3% Gold Find
In addition, a distinctive increasingly-impressive border will surround your character portrait in the in-game party frame to denote your Paragon progression, with a new frame earned after every ten levels. Your Paragon level will also be visible to other players wherever your normal level is shown
http://us.battle.net/d3/en/blog/6968517/