Absolutely, no doubt at all.

None of these, either together or separately, are required parts of an operating system.
All an operating system really is required to do is allow a user to run programs of their choice. ANYTHING beyond that qualifies as smart.

Services:
Xbox integration: I have access to all my xbox friends and their avatars and information. I can send and recieve messages from them. In the future there will be chat and game invites and most of the features already present on the xbox itself.
Zune: A huge catalog of drm-free music at competitive prices. Also available is the Zune Pass, of which I've been a subscriber for a few years now. I can download whatever I want, whenever I want, wherever I want, and however much of it I want. No hassles. I get to pick 10 of my favorite songs each month and they're mine forever, no questions asked. I can have only my phone, and stream the vast majority of songs available on the marketplace seamlessly. If I'm at my computer I can use the fantastic software client to manage/buy/play my music. If I'm at the library, I can log into the zune website and stream music through the web browser. I mean the abilities are astounding! Plus every night I go to bed, plug in my phone right beside me nowhere near my computer, but when I wake up the next morning all my new music and podcasts from the computer are magically on my phone. New pictures and music I have on my phone are on my computer.
Windows Live: Anything from any of my windows devices can be synced to each other seamlessly through WL Skydrive. I take a photo on my phone, I can set them to automatically upload to Skydrive and from there they can go anywhere: flickr, my computer, etc. I don't have to go through a "share" menu, it just happens.
Then there's the social integration. I don't have to load up the facebook website or even the app. Its integrated into each person's contact.

Community:
Granted there isn't anything in the windows world, that I'm aware of, like the "communities" that gather around open source projects.
That said, consider that there are TONS of blogs and podcasts by Microsoft employees about all of their projects. For Windows Phone, there is the Windows Phone Radio podcast that is run by two developers from the team that develops Windows Phone. Furthermore, its not just them broadcasting, they answer emails, ASK QUESTIONS OF THE USERS LISTENING, and generally CARE and care PUBLICLY. Then there's the Zune Insider podcast if you care about the Zune side of things, which I do. Its incredibly informative and since Window Phone users use the Zune software client on PC, its informative since one of the hosts is a developer who works/worked directly on that. They consistently talk about feedback they've received and what they're doing to act on it. Just the fact that they let their users know that they HEAR what users are saying and take it back to the team is amazing. NOTHING like that exists in the Nokia world.

Applications/Development:
I'm not going to espouse an app market as the best feature about a phone. Android and iOS have larger markets. I just want to say if you care about that sort of thing, WP7 has an excellent market that has a lot of apps in it and its consistently growing by leaps and bounds.
As far as development goes, ITS MICROSOFT. They make some of the best development tools and environments that exist.
Lets face it, developing for the n900 when it first launched was a joke. Thats partly why it never gained the sort of traction that could have inspired Nokia to put more support behind it. It got better when you could use Qt to develop for it, but that was always more of a work in progress than a fully integrated experience.
With WP7, you're using proven tools with EXCELLENT documentation. Development is a breeze. Thats all that needs to be said.

WP7 isn't a smartphone, its the future of phones.

I can go on, and I probably will to correct some of the blatant idiocy I'm reading in this forum, but for now I'm going to get some pizza.