I'd say its a success when people realise its iPhone vs. Android vs. Windows Phone, although seeing as BlackBerry is still (the most) popular in the UK (due to kids), I feel we have a ruddy long time to wait.
The issue is it's not. It's still Android vs. iOS vs. Blackberry. Blackberry 10 will pass WP7 marketshare numbers almost immediately just based on the number of current BB users who upgrade from BB7 devices to a BB10 device - and possibly the number of BB defectors who will go back to RIM. They still have a huge lead on WP7 - especially in World-Wide Marketshare (when you get out of the ComScore US Marketshare numbers bubble) and they won't be ceding that to Microsoft anytime soon.
Microsoft also has little to no momentum in the Corporate sector - much less even than iOS and Android, nevermind RIM who could probably beat them there with BB6 devices, even. RIM has a niche that can keep them afloat, Microsoft doesn't. They did have a decent chunk of the corporate sector with Windows Mobile (which is why WM still has higher marketshare than WP7), but they are losing that.
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As for the poster above: WiFi tethering has been tested by users and it's a possible trigger point for the WiFi issues on WP7.5 devices (the issue popped up in the Mango update), so if you don't use it the chances of you experiencing that issue is close to Nil if not exactly that.
We were all beta testers, at least all of us who got 1st gen devices on release. It's common knowledge that the OS was at beast RC status back then, and there were a number of critical bugs and ommissions on release which persisted until NoDo and/or Beyond.
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To the other poster, yes smart deviecs affect our Quality of Life. I don't think I need to explain this any further. Trying to deny that doesn't make any sense to me, except for the sake of argumentation, which I am not interested in ATM.
However it seems odd that people would disagree so fervently, but respond in a tone that would imply that you've impacted their QoL just by giving opinions and/or observations they don't like or agree with. It's just a smartphone OS, right?
I mean, being able to check into flights or book Amtrak while on the go with a dedicated app doesn't increase my QoL. Being able to order food on a phone doesn't. Being able to chat in am MMORPG from my smartphone doesn't. None of that. It's just fluff

Malfunctioning smartphone functionality is totally ignorable and it's just a phone so we should ignore the software and/or hardware defects on any device (while users here say they moved to WP7 cause android was Buggy and laggy, as if it matters cause it has no impact on your QoL as far as some here are concerned, right?). Astounding levels of hypocrisy herein.
2. we now have AT&T and Nokia both pushing WP , 2 years ago they dint even want to talk/look at it , now people are talking!!! and positively on top of that!!! lol
Does not compute. AT&T was announced as a premium partner before WP7 launched. Nokia has been on the WP7 bandwagon since forever since they don't really have much of a choice with their "burning platforms." Of course they will push it.
Things look different when you go to Sprint and Verizon, or even T-Mobile with their lack of any Mango devices above mid-range (which is sort of confusing for WP7 since all the devices technically are mid-range, just the screen sizes and internal storage/LTE support differ).
What people are talking, tech blogs and their commenters, or average people around town? So far I've seen one other person with a WP7 device (a focus), and that was over a year ago and 1300 miles away from where I am now. I haven't seen any since I've been living here but I see tons of Androids, iPhones, and Blackberries (Torches and Bolds mostly, a Curve here and there).
I have had people ask me about my phone though, since it was something they had never seen before (the User Interface, etc.), but they didn't seem impressed to the point that they'd want one (nor am I interested in selling phones for T-Mobile or AT&T).