At the moment, users will have no problem installing alternative web browsers such as Chrome or Firefox to the desktop environment of Windows 8. The Metro UI, on the other hand, currently offers Internet Explorer exclusively. This has been seen by some as a potentially major shortcoming, since Metro is so central to making the most of the new software.
Fortunately, perhaps to avoid the sort of lawsuits that Microsoft has encountered previously when pushing IE on their users, they have created a separate application class that bridges the gap between environments. This app class, which currently seems to be restricted to web browsers, allows developers to fit into Metro without losing access to the Win32 APIs that they need to handle many of their necessary functions. These Metro-style Enabled Browsers will still run in Desktop mode if desired, but should offer users the choice they need.
The biggest name to confirm their interest in this development is Mozilla, who will be bringing Firefox to Metro. It will be a significant overhaul by most accounts, but developers have implied that they expect to have at least a beta ready by the end of the year. This puts an official release somewhat behind the anticipated commercial release of Windows 8, but is definitely better than a rushed and unfinished product.
There are still some problems left to be addressed in the web browsing experience of Metro that will hopefully come out more in the near future. Most importantly, the situation regarding cross-architecture distribution and performance is vague at best. Because of the way that Windows 8 restricts desktop access on ARM devices, all applications must be acquired via the Windows Store. It seems unlikely that Mozilla, Google, or anybody else who might want to compete with Microsoft’s browser of choice, will want to tie themselves that closely to their competition.
At the moment, only one browser can be selected within Metro at any given time. This means that users will have to tie themselves down to one selection. Few people seem likely to mind that sort of limitation, but it is important to be aware of.
Of course you can still have multiple options installed, but as users of the Consumer Preview may be aware, when a browser is not set as default it will open exclusively in the Desktop. Tying users to the desktop in such a way would seem to be against the philosophy of Windows 8, though, so perhaps we can expect to see this change in the near future now that the new browser app class has been made available. It is an especially important consideration for the previously mentioned ARM device users for obvious reasons.
Overall, this is good news. Keeping in mind that all we have right now is a Beta release, indications that accommodations are being made to increase flexibility point toward a positive transition. It would be nice if there seemed to be the possibility for competing browsers available at launch, but at least they will not be long in coming.