I hope they switch off metro by default, scrolling sideways like that is annoying and the start menu is practically useless.
MW
It (the Start screen) will unquestionably be on by default. There is absolutely no way Microsoft are going to ship Windows 8 with the gateway to its flagship feature, and the future of the platform, disabled.
I do however think there should (and will be) a supported way to revert to a 'classic' start menu, for two reasons -
The first is, I think if it can be disabled without resorting to hacks it will go a long way to mitigate a lot of the complaints from the vocal minority. If you don't like it don't use it, and in my opinion even if you never run a Metro style app (not that disabling the Start screen would stop you) there are still a lot of reasons to upgrade especially if you can get the discount pricing. You'd hope that Microsoft have learnt to keep the vocal community on-side.
The second, and most importantly, is for corporate use. As it stands, and I think this will be true for quite a long time, the metro apps are geared towards consumption. News readers, weather apps, social apps, games - the sort of stuff I wouldn't want to encourage on a work computer. That's not to say I don't ever think you'll be able to be productive on a metro app, but the real work is still going to get done on the desktop applications. Mail apps, notetaking apps - even the Metro version of Office - are just not going to be as powerful as the desktop equivalent because it's completely at odds with the Metro-style guidelines.
It's also a support nightmare waiting to happen. Hypothetically - could you imagine if you rolled out Windows 8 in its current form over the weekend? I'd take Monday off unpaid just to avoid the worst of the backlash. "The start button just takes me to a green screen", "Where are my files?", "Which control panel are you using again?", "How do I shut the thing down?!". Oh, and the Intranet won't work because Metro IE10 doesn't support plugins - use the
other IE10. If you think people hated Vista or the Ribbon, this would probably eclipse them both.
Yes, it is silly to imagine the above scenario at this point in time, but no more ridiculous than people making purchasing decisions based on a developer preview. The point is there will be lots of changes before it reaches beta, let alone hits the shelves, so making your judgements and drawing your battle lines now is a bit of a waste of time.