You see the big problem here is that Microsoft can say Windows RT (Windows on ARM) is a specialized OS. It will not be for sale to the general public (like Windows Phone OS). It will ALWAYS be preinstalled by the manufacturer. This is much like Google’s Android and Apple’s iOS. Both of these operating systems have default browsers that cannot be replaced.
The fact that Microsoft is leaving in a “desktop” mode for Office does not automatically grant third party access. In fact Microsoft’s definitions for their Apps are less restrictive than Apple’s. Remember Apple will not allow any App that replicates a core function of their device (that extends to the iPad too). Microsoft is allowing this and there are plans for Apps like Polaris Office and others to be able to operate on WindowsRT (again an OS designed for ARM devices only).
On the consumer version of the OS (for x86/64) there are no restrictions (the programing model is more complicated but still possible). It is also not true that Microsoft is not allowing any competing browsers on Windows RT (although this has been reported a couple of times). They are only preventing third party browsers from access to the “desktop” mode in Windows RT.
Although we do not completely agree with Microsoft’s decision here (and a few other things about Windows 8) we do not think they are doing anything that has not already been done by other tablet makers. If this really does fly we would fully expect to see Apple and Google brought up on the same charges as there is no way to change the default browser on either of their products. In fact for a long time you could not select any other search engine but Google on both iOS and Android yet there was no public outcry about this.
Personally I think this is nothing more than Mozilla complaining (again). They have already stated that coding Firefox for Metro is very complicated so perhaps they are hoping that this will force Microsoft to let them use a simpler version of code instead of the Metro only code they have to use to get things rolling on Windows 8 and Windows RT. This becomes even more evident when you consider the fact that they have completed their Metro Style Enabled Desktop Browser version of Firefox for the x86/64 version of Windows 8. To get this on Windows RT they will have to develop a Metro only version as that is all you get on Windows RT if you are a third party dev. Only Microsoft has access to the Desktop in Windows RT. So it looks a lot like Mozilla wants to complain rather than do some extra work that, in their opinion, might not pay off for them.
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