markee174: Yes, there's a proven interest from users in Firefox for RISC OS; however almost all of the people with the skill and inclination to continue the port (which now, let's face it are the boring bits of fixing bugs etc.) will have another machine available on which they do the majority of the web browsing. Indeed, they'll even need one to do the building with gccsdk as the current RISC OS hardware is inadequate.
Without the need to scratch their own itch, it's not particularly alluring.
Also, as has been made clear many times before, getting Firefox working won't magically bring with it Flash or Java - two of the things which people often criticise RISC OS for lacking.
timephoenix: "If they want to prevent RO become a hobby platform [...]"
Anyone who thinks RISC OS isn't already a hobby platform is living in a dream world (or living in the real world without much money).