If there's any chance of the N9 taking off in the UK, it needs to be in phone shops, subsidised on contract.

I don't really care that it's available full-price sim-free through the usual suspects. I'll be getting one even if it involves a weekend trip to Finland, because I'm gullible and the N950 is Bloody Great.

What I would like to see is a bit of word of mouth and people wandering into phone shops, trying it, and getting an upgrade/new contract.
I truly believe that it's the first Nokia handset post-iPhone that you can give to the (mythical) Man On The Street and it'll impress them almost immediately.
If it's only available sim-free at £500+, any potential purchase interest in non-fanboys is killed stone dead. Less adoption = Less reason for Nokia and 3rd parties to continue supporting the phone/platform/ecosystem.