When Amazon's Appstore rolled out last week, we glossed over one detail that merely seemed neat. Today, we're inclined to saythat Amazon's Test Drive may be the most significant piece of the whole thing. Basically, Test Drive allows US customers to take apps for a spin at Amazon.com, with all the comfort that their tried-and-true desktop web browser brings -- but rather than sit you down with a Flash-based mockup of the app, Amazon is giving you a taste of bona fide cloud computing with an Android virtual machine.
In other words, what you're looking at in the screenshot above isn't just a single pro
