Some things, like the alarm app, really annoy me, but overall the interface is nice. If only there were more third party apps, we don't even have facebook or skype on the marketplace my phone supports (which is hardware locked dammit!).
Ah, I only have experience in the US store where there is Facebook, Skype and a ton of other good stuff. I suppose its only a matter of time, but for now I agree that is kind of unacceptable .
We have full-featured instagram (3rd party app call led instance), we have a Facebook app and you can definitely upload pictures, and there's even a snapchat client too. But I agree, the app situation is undoubtedly worse on WP. I don't use very many apps personally, so it works for me.