2010 tops use a cable and spring. The spring will be "hidden" right above the back doors, and the cable will run inside a fabric sleeve to the front. The advantage is that when you flip the sunrider portion (giant sunroof) forward, it snaps into place, and you don't need to work the plastic canards (wings) into the door surrounds. It's a neat feature.
Visually, no you can't tell from 5 feet away. You need to get right up to it, and undo a bit of the fabric to see if the spring is there. Fairly easy if the top is off.
The door surrounds will be different too, but just slightly: it's a smooth "shelf" for the top to sit on, rather than a slot for inserting the canards.
EDIT: Cable top is only on 2010 and 2011 Wranglers, and only on Factory tops.