As someone who switched from a browser based OS, WebOS, to iPhone 3GS, and now to Android, I can tell you I will never go back to another laggy HTML based OS. If anything, I'd like to see Android move away from its VM based apps to something like Apple's native apps. Many apps ran better on my 3GS than they do on my much more powerful S3. Mozilla is going the wrong direction on this one. Native > Java > JavaScript
The whole idea of using HTML, CCS, and JavaScript as the back end technology for a low-end smartphone is nuts. Even the best HTML rendering engines are CPU and memory hogs. CSS was never designed for and is nearly impossible to hardware accelerate, and JavaScript is notoriously difficult to optimize and even the best VMs like V8 run orders of magnitude slower then Native code, while the VM itself takes up a massive amount of memory.
I get that Mozilla wants to put Firefox on a phone. Fine, but first, focus one building a competitive browser. At the end of the day, I want a responsive fast phone, like the iPhone or Galaxy S3, not some dog slow HTML monstrosity.
Mozilla please just invest your limited resources on making a lean browser that can compete with Chrome!