Advise for neck strap

+1 for the Black Rapid. I like it because I can easily adjust the lengh. When in more crowded areas I shorten it up. Just make sure you tighten down the screw that goes on the bottom of the camera until the rubber donut "squishes" out. I've read some users have had the screw back out, something I've never experienced thankfully.

Heard good things about he OPTech as well, never tried one though.