My wife and I have had our Lumia 920's for about 2 weeks now and I can't say enough positive things about it. I used to believe I would never leave my beloved Blackberry (nothing in the world does email like BB imo......and of course BBM is just sexy!) but here I am a Lumia 920 owner and couldn't be happier.
As you said ID, the best smart-phone I've ever owned as well. Live-tiles truly is innovation over the standard icon-grid from droid or iOs devices and I'm finding it actually is a rather large time-saver as well.
The fact that my wife can use the touch-screen with her gloves on and not freeze her pretty little fingers (it gets cold up here in Canuckistan!) is also a plus. MS Office on my phone.........HUGE plus. Skydrive, about as seamless and painless as "the cloud" gets.
Hands-down the best phone UI in existence......period. The screen on the lumia (considered to be HD+ with its "better than HD" res of 1280x768) is FAST! There is absolutely NO lag on that screen.....ever. This makes browsing and scrolling around in IE 10 a dream, especailly when you can take advantage of the superfast LTE network speeds.
The phone itself is PENTABAND which means it works on more carriers/networks and my wife and I were lucky enough to get phones of the first batch shipped to our carrier which ended up being carrier-UN-locked. Now when I travel I simply pop another SIM-card from a different carrier into the phone and boom I have a phone to use in another country. Bonus!
Nokia also has (better than most) free apps including Nokia Maps (which is on par with google maps in my opinion) and Nokia Drive (great turn-by-turn GPS software). For both of those apps you can download maps so the apps can be used in your more frequented areas without incurring higher data costs. There are quite a few very useful free Nokia apps (I won't go into them all) but one they just added a few days ago is called "PhotoBeamer". This app allows you to point your Lumia 920 at any internet-enabled screen and via QR-code technology "beam" any picture on your phone to said screen. The absolutely simplest way to "show" family/friends a photo from your phone, give it a go ID you'll love it!
Anyway, I could rave and rave about this phone.......suffice it to say it has integrated with my Exchange environment and my Win8 desktops/notebooks so easily I wonder if Microsoft has secretly stolen the "consumer-usability-and-ease-of-use" crown from Apple somehow! hehe