Well as most of you may have heard Google announced the Chrome Web Store at Google I/O.
From the demonstration at the event it seems that its a Web Store done right (unlike the Java Store).
There was an impressive showcase of 3d games powered by Unity3d (the standard web plugin).
I have confirmed with the devs that Java Applets will be supported (as well as any other plugins that runs in the browser, flash, native client, silverlight, etc). Its essentially just a way in which a desktop icon is added to your computer and when clicked will open the browser.
I reckon java applets (using LWJGL or JOGL) could work really well here, if you use a proper certificate users should only get one security dialog which is shown the first time applet is run (which isn’t bad for a one time install).
If the store does well this could be a pretty cool way to monetise java games/apps (would also make sense for Android games/apps as they can share code bases).
Also it looks likely the Web Store will be the main way to install apps on the upcoming ChromeOS (which does run java applets, but atm is unclear if java will be installed by default).
more info and video here