[crazychrome]

Sorry for the late reply. I made couple of chrome extensions and apps last year to test the effectiveness of Chrome Web Store as a distribution channel. Now two left: PayableForm (app), and News Tracker(extension). Both were build during weekend, and both were little marketed.

The result is disappointing (for extensions). The installation ratio of chrome extension is never more than 0.2%, while chrome app is constantly above 0.5%.

Google did downplay extensions. Around Nov last year, Google put Apps above the extensions in the search result list. Google also default to expand categories under "Apps", resulting extensions down to the 2nd to last of the list in the left side bar, just above themes.

On the packaged app front, maybe you can use good-old-drag-n-drop.