At J and Beyond 2012, the idea of a Joomla! App Store was discussed. Now, a couple of years later, we will soon see the arrival of the Joomla Extension Finder. Also known as "Install from web".
When the plugin is installed, you can browse the JED from within your Joomla administrator, and install extensions with a couple of clicks. See the below video for more info on this exciting new and time-saving feature.