There isn't much that's totally original, really, but they sure did a 'swell job at implementing it. The character switch mechanic is cool, although I've seen similar implementations before, it's just that R* put it to good use in V.
And nice job with the pie/radial menu, too.
*inb4 GTA5 HUD mod for GTA4*
This was posted on the PS blog by someone that I think is a Rockstar employee.
http://blog.us.playstation.com/2013/07/09/first-grand-theft-auto-v-gameplay-video/
If GTA V does end up being a launch title on next gen consoles, it'll probably drive their sales sky high.