I am really glad to see the new Mozilla Mobile initiative. Mozilla 2 is a great time to undertake most of these changes. The thing that really sucks about developing for mobile devices is the browsers are pathetic at best (with the notable exception of the iPhone). Wireless speed is still an issue in some cases, but with 3G coming about, it’s not the biggest concern if you can manage to keep things slim. XUL on mobile will be very interesting. If done right, it would allow for client side applications that don’t suck, yet have the lowest barrier to entry (JS+XML = Easy). Not to mention you can target a bunch of devices with one download and code base. Don’t forget you’d still be able to do rather realistic debugging on your desktop.
Hopefully by the time this all comes around, data charges for mobile will drop significantly. The iPhone is still $60 for the cheapest plan. If you need more than 450 minutes of voice, you’ll be spending even more. While interest in the iPhone is high, between hardware and plan costs, I think it’s still to high to attract the masses. There’s still time. Firefox 3 isn’t even out yet. Mozilla 2 is still a little while away. I suspect these prices will be dropping as other providers try to compete with the iPhone. A price war is very likely.
One question remains: will it run on the gPhone?