Owneer of Lumia 800... Avoid like plague
As beautiful as the phone is, and it is beautiful, it's only as good as the OS. WinPhone is nothing more than a beta product right now.
Fat fingers? Get used to QWERTY keyboard as there's no old skool phone keypad keyboard available.
Crap speller? Buy a pocket dictionary. Whilst Android allows some form of guess work for those words that bamboozle you, don't expect the same courtesy in WinPhone. Sure you can spell tomorrow with the occasional wrong letter... But only if said wrong letter is next to the correct (i.e. E instead of R)
Nosey girlfriend? You're fucked if you get a text as she happens to be looking at your phone. There's no option to turn off message notifications. There's no decent SMS apps available either.
Tethering? I've read countless sites saying 7.0 allowed tethering. I can't find it in 7.5.
Auto time? Nope. Manual. Although it does adjust for BST, it'll only give you the extra hour. If your clock is wrong it'll stay wrong until you manually correct it.
Email search? Sure. But only if you download your entire email inbox. Searching passed 7 days is impossible unless all your mail items are available. On your phone.
Background data usage? Expect a big bill if you go abroad. I turned mine on whilst out of the country to retrieve an email. Whatever the phone did during the 10 minutes or so data was turned on cost me 6mb of data usage. Emails only download header information and blank text until you hit "download images", that's a lot of data going somewhere.
Copy and paste functionality? Crap.
Big gamer? £2.29 is the standard Xbox game price, £5.49 for Pacman. There's no Cut The Rope or Words With Friends/Hanging With Friends or Angry Birds Seasons/Rio to name but a few.
Customisable? 8 colours in which to use for your tiles. And that's it. Big shortcuts. in 8 colours.
As a fan of xbox gaming, the achievements are the only thing keeping me on this phone, I miss almost everything about Android. I'm holding out for Tango, if it's rubbish I'm moving back to HTC.