My top request for google chrome is a user script plugin like Grease Monkey from firefox.
by having the ability to run user scripts in Google Chrome I can guarantee that plain old firefox will be history, that is the #1 plugin that is prventing current firefox users from switching to the fastest browser ever made. It unlocks further capabilities just like it has done in firefox, just by adding this plugin, you can then create a user script like megadownloader that enables the ability to download any media file type from any webpage just like DownloadThemAll.
By creating a plugin similar to that of grease monkey in firefox (I would recommend naming it Chrome Metal or Google Metal

, this will achieve two goals with one effort

Add user script support to google chrome and adds DownloadThemAll to chrome