I would not count on other browsers supporting .maff although the plugin does also create mhtml which extends its usage to IE and i think a a few other browsers? Ideally, it would be great if MAFF or something like it was a standard across all browsers but I’m guessing that this takes us right down the road of file format control and spec preference. They will advance or create new formats to do what MAFF already does and go into the areas that we are talking about with media packaging. Sony and Apple are already releasing such tech as Lucas mentioned in his post.
Not to mention the name Mozilla Archive Format as being supported by Safari, Chrome, IE? Like everything, there is a game to play.
Luckily, Firefox is very pervasive at this point. Even if you dont use it, its easy enough to install and use when you need to (ie. loading a maff file). And of course, being a ZIP file, you can just extract the files.
What I would also like to explore is building a tool to create MAF files outside of Firefox. I did this when Mozilla Prism came out a few years ago. I created a bookmarklet connected to a little web service that generated Prism WebApps on-the-fly.
This was immediately after Prism was announced so their was no FF integration like their is today. But even with that, I liked the idea of a having a stand-alone Prism browser installed on mac or windows and being able to make Prism WebApps from Safari, Chrome, IE, Opera etc.
The same thing can be achieved with MAF and any other ZIP based archive format.
It would also be nice to open MAFF with a lighter version of FF. Posibly even the mobile browser fennec.