Just to mention, I don't have an unlock code yet, the phone is locked to o2 and I'm in a T-Mobile contract so I haven't been able to test any phone functions (Phone and SMS/MMS).
OMG Zune is awesome, It's never been available in the UK before but the whole experience is great. People put down Zune syncing as a negative but imo it's a much nicer and better way of syncing music/pictures/videos to your phone than having to connect, mount and then drag and drop.
The application itself on the phone is great, certainly better than the iPod app on iPhones. It's nice seeing your last played artist as the background in the app and the live tile, when playing music you can see what's coming next, swipe left to right to skip tracks and there's a now playing type feature that will come up regardless of where you are just by pressing the volume button.
Zune Pass is awesome, it's slightly cheaper than Spotify which is what I was previously using but the best bit is rather than just streaming (and then adding to a playlist and making it avaliable offline) you actually download the music from the store like you would do if you were buying it, it becomes part of your library with all information, tags and cover art. You can also, like spotify, stream.
Microsoft have totally reinvented mobile apps and, while there aren't many of them, the majority of WP7 apps are 1000x better than the same or alternative app on Android, iPhone, WebOS and any other platform you can think of. Apps look sexy, there's no more going in and out of sections to do a specific action, you simply swipe left to right.
If you're reading this, you've probably seen examples before and know what I'm on about but if you don't... Take twitter for an example. With the android app, once it's loaded up i'm presented with a load of options... Tweets, Mentions etc. I need to go in and out of these if I want to view more than 1 thing. With WP7 you're presented with everything, your timeline loaded first, swipe to the left to see mentions etc... There's no jumping in and out of different sections.
Apps are also graphically rich, there's little to no plain black backgrounds (apart form in general apps like messaging and calendar where you wouldn't really want anything else).
The games on this platform blow away anything else I've seen on a mobile device. They're pretty much xbox live arcade games but there are other great non-xbox games aswell. It ties in with Xbox Live pretty well, you earn achievements and games go in your played list. Each game has a "trial" option where you can download a demo version before buying.
Anytime I read Android Fanboy's comments about WP7 they always point out how the interface is rubbish and tiles are too simple. I disagree. Tiles are basically widgets just like in Android. Some are live, they display information which are pushed to them or they show some sort of animation... just like how in Android widgets can show information. Some aren't live, these would be the equivalent of taking an app from your app drawer in android and putting that on the home screen. Instead of swiping left to right to see more, you swipe up and down. Instead of pressing a button to view apps, you swipe to the left. They're pretty similar when you think about it.
Scrolling is silky smooth and the whole experience is Much quicker compared to android (and I'm comparing to Cyanogenmod with Launcher Pro, not Stock). The interface and Typography is consistent throughout and the typography is awesome.
I have a HD7 and don't know weather this is device specific or OS specific (however the phone does seem to have a smaller battery than my desire). Today I got 12 hours use. 4 Hours of those I was playing music. The phone is constantly being turned on, new things being downloaded, wifi is on all the time due to me not being able to put my contract sim in yet. On android I averaged about 7 hours, this was with 1 hours worth of music.
What's not good compared to Android
There IS multitasking, to some sort of degree. I don't really know the specifics but what I do know is that Last.FM can play music in the background and Twitter seems to update itself in the background. However what it is hard to get used to is switching between apps. There's no kind of "running applications" menu or anything like that, when switching you need to go via the home screen and load the app. This isn't a biggie but it can take some getting used to when you're used to holding down the home button.
Games are quite pricey, they're better than any other games I've seen on a mobile but nevertheless, pricey. They range between £2.50 and £6.00 from what I've seen. Apps aren't pricey but there certainly seems to be more paid apps than free apps which coming from android is weird. However, this may be down to the fact that it's a new platform and there aren't that many apps yet.
Closeness and Customisation
The fact that the device is closed doesn't bother me that much however there are a few things which are annoying like the fact that you can't load custom ringtones. Customisation also doesn't bother me that much but it might be a biggie for some people. You can chose between a light (white backgrounds) and dark (black backgrounds) theme and then choose between a set list of about 6 colours for tiles. That's about as customisable as it gets, you can't set individual colours for tiles or anything like that.
This is not really a negative, it's a new platform and there aren't many apps, this is acceptable imo. But to some people, they might not like this idea. If you're an "App Whore" and can't live without having 10s of thousands of apps to chose from then windows 7 phone isn't ideal for you yet.
There are a few bugs to be ironed out, sometimes apps wont launch. Having said that, it's not like Android doesn't have any bugs even now...
IMO, WP7 has more positives over Android. There are a few niggles but I await to see how Microsoft deals with them and how the future of this platform shapes up. It certainly beats any version of android pre 2.0 hands down. I hope Google bring out something impressive with Gingerbread!