I would be happy enough to just be able to use the Amazon appstore in the UK as is.
I don't trust Google really with my details but I do trust Amazon. (They are fair and reasonable and you can phone them up if you need to all though it is seldom required.)
If I could use prepaid cards with Google Play it might be a bit better but tbh I deliberately create a new Google account fairly often. (And I definitely don't want the same account on phone and tablet)
I am probably in the minority but I trust MS and even probably Apple more with my personal data / credit card details than Google.
(I like WP7 hate iOS and use Android so I think I am fairly unbiased). I think I will get a Lumina 710 soon.