[jbottigliero]

My immediate take-away was that this was some sort of stand-alone application or utility. After realizing it's a hosted service, the real benefit comes from being able to slug a URL and pass it along.

There is still a number of folks out there that might understand there is a mobile web, but might not necessarily grasp responsive design, or the variety of screen sizes and what they mean for a design... the initial UI on the resizer alone explains it pretty well.