Coming from a firm entrenchment in the iOS world (2G->3G->3GS->4->4GS), it's been quite an enlightening experience so far.
The first thing that struck me was when the AT&T store rep took the phone out of the box and handed it to me to examine while he set up my account for it. In all the pictures I'd seen in reviews, and all the comments, I honestly expected the phone to be a lot thicker than it is. The build quality was solid and very impressive, and the phone is just beautiful to behold. The weight....yes, it's got some weight to it. To my mind it definitely adds to the "solid" feel of the phone, and it is very, very well balanced across the device. The only possible complaint I could muster on the physical aspect of the phone is that unlike the iPhone, it doesn't fit in the 5th pocket of most of my jeans.
Once I turned on the phone....wow. The screen is gorgeous. Very crisp, with bright popping colors, incredibly sharp and smooth even coming from the Retina display of the 4/4S. What surprises me even more is that even turning down the brightness to low the screen STILL has a lot of pop to it, and I've got no issues with the brightness at that level, whereas on the 4S I'd be running at least half-full brightness.
Have not as yet played too much with the camera, but what few pictures I've taken looked fine to me, though I'm not a big enough picture taker to really offer an objective review. The pics I've tried in the dark came out surprisingly well, and I've been very impressed just playing around with taking videos.
Call quality was rather impressive, especially as its been one of my issues with the iPhone. When talking with relatives (I had an iPhone 4S, they a 4), at least two or three times a call I'd have to ask them to repeat something as it just got too garbled to understand. So far that has not happened at all with the 920. Audio comes in much clearer and even with the general static of a cell connected and having an iPhone on the other side I could understand every word.
Music quality so far has been impressive, especially with the Dolby Headphone option active. I'm hoping to spend some time this weekend to do a more thorough check of the sound quality from both headphones and the speakers, but so far it has been quite positive.
It's only been a day, and the battery seems to be doing quite well. Unplugged around 7am, 3+ hours of music listening (with Dolby enabled), playing around with maps, a bunch of text messages, watching some youtube vids, downloading (WiFi) 2+ gigs of map data, and probably 2 hours spent mucking with settings and working my contacts, and the phone is at 40%. And that's still on the first charge, and on a first release OS. I figure as I get a few more cycles in the battery will get a bit better, but even now I can't complain. REALLY looking forward to when my wireless charging plate shows up!
Windows Phone 8....has definitely been a transition. On the whole, I find most aspects to be preferable to iOS. The Live tiles are a definite treat and address one of the biggest complaints I had with the iOS UI. And they way they intergate social media information and contacts and apps and such.....to me this just feels like how its supposed to work. I don't have to constantly jump between a bunch of apps just to check email, facebook, twitter, etc. I'm still a bit surprised to see something like this coming from Microsoft but I absolutely love it! Now I just need to start figuring out the little things...like pressing the volume button to bring up the drop down controls for music when in another app and such.
The only downsides I've hit so far with the OS is that the music app, especially coming from the iPhone world, really leaves much to be desired. Organization isn't terrible but isn't great by any stretch, and I'm really confused on this reliance on "artist image" with regards to the Live tiles and lock screen. Seems odd that I can't just have the album art show on the live tile and lock screen, but from what I can tell this is just not possible with WP8. Hopefully an update might be able to address that, as for a lot of my music I doubt I'd be able to get "artist image" for them (I listen to a lot of soundtracks and foreign artists).
The tl;dr version...overall I'm incredibly happy with my Lumia 920, and with WP8, and don't see myself going back to the iPhone at all.
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