I realise it's only the dev preview, and i won't hold it by this impression, but so far it's all i have to go off. And personally I hated Windows 8 as it was - even if i liked it - there's no way i would pay to upgrade. I personally think Metro is pointless and a hinderance, and within the people i've asked at my uni, and home, i've met only one person who had anything favourable to say about it, (And he is a big touchscreen user - for which it does make a lot of sense). To me it's a touchscreen UI, that is rather lazily thrown into a PC OS so far. Maybe they'll change it drastically, and I will rethink my opinion - but as it stands, i'll stay clear. Also Windows explorer does not need a ribbon - though there are 1 or two new useful options on it.