Just to be precise, only the game engine is open source. "Images are licensed under a Creative Commons License and are provided separately," and this CC license is BY-NC-SA which is neither FSF- nor OSI-compliant.
This looks like a good thing for the liberated pixel cup to be used to replace those assets.
http://lpc.opengameart.org/
Looks like they are ceasing development because of technical limitations and user engagement problems that come with it being an HTML5 app vs native app.
Is there a way to release an HTML5 game that isn't open source (viewable code)? Other than obfuscating the code isn't it necessarily available to the user?
You can wrap it up inside a web view and deploy as a native app. This is what frameworks like PhoneGap are for. Given the game is available in the iOS app store, this is probabably what they did, assuming they didn't write their own wrapper application.
obfuscating the js would still be more important, as there are probably some simple hacks to get all the javascript back from the web view or the js file used by the app.
Will be interesting to see if this benefits the original game any later on. Maybe people will write Android games using it and contribute back the ability to the original, etc.. Or maybe they won't, etc..
Doesn't work in Firefox
There is an issue open[1], looks like a fix is in the works.
Excellent, this is great stuff. I wish they had released a separate HTML5 Game Engine. At a glance, it looks like everything is tied pretty closely to the game itself. I've been looking at engines like Isogenic and Construct 2, but here you have a large HTML5 game larger than most had been able to demonstrate. Plus, its open source, where the previously mentioned engines are closed source and require a license purchase, although Construct 2 has pretty good documentation on how to make games. I really like what Wooga did with this.