Yes...and no
File handling is not native. In other words, you can't mount the phone like a USB stick and drag and drop to it. I miss that, but that being said, I do like the closed environment. Far less opportunity to hose the phone with malware IMHO.
Where iOS and Android are app-centric, WP7 is 'people-centric', meaning that the OS sees contact and messaging data as a resource to be let out and about to mingle with the phone's various hubs. Hard to explain, but works really well. I think it's highly intuitive.
What I really love about the phone is the Metro design. It's so easy to see and interact with. No more pages of miniature Chicklet-sized icons and squinting to see stuff. The Live Tiles are so useful as quick sources of information I don't know how I lived with Android for so long.
I had no problem getting and Exchange Server account set up as well as GMail or Facebook. Easy. And I always use the One Note integration in my Office Suite at work, so that's a really plus.
When Mango hits, anyone who has any appreciation of how a smartphone should work will see WP7 as the real leader in mobile OS's