Photoshop mock-up
Intelligent forms should make the JFC experience more inviting. Subtle hints are more user friendly than "ERROR ERROR" after move, click, move, click, move, click, click, etc. The inspiration comes from the Web 2.0 movement, but the concept is very old. Very 1999 I guess.
This is just a Photoshop mock-up by myself, but according to some trusted sources we might see this functionality very soon.
Check out Jan Erik Paulsen on Twitter.