Apps DO matter more than you're making out...
The app argument to me, is not a big deal. Especially when taking into account quality of the app. Android may have a massive number of apps, but a large number are not worth installing. I've yet to need an app on WP that wasn't available and wasn't better than it's Android counterpart.
I'd disagree. As someone who uses Android extensively (Motorola Atrix, UK), I also have a Nokia Lumia 710 (almost literally given to me - free phone, ?4 per month as a second line on my contract...).
I'll comment on what I like about W7 elsewhere, but the apps thing is an issue. At a personal level, I am not a games player - the odd game maybe for 10 minutes (likely to be Angry Birds or Pool etc), but most of the time not so much. WP7 has simply not got enough apps that cover popular services, sites and so on. I was surprised that more were available than I expected to be though. However my bank, the car parking service and many others I use regularly are not available. In today's phone/cell world, that just isn't good enough.
As a general user though, I suspect this is an issue. Over here (UK) at least, there are loads of adverts on TV that tell you to download an app - the apps are ALWAYS advertised as on the "App Store" for Apple, generally on "Google Play" for Android and er, never so far on Windows Phone. A few are available but the majority of apps are not. It's frustrating when Android is still second best as is (sadly) often the case, but Windows Phone and Blackberry... realistically they're far far behind.
As for the quality - ignoring the "quantity" of poor "quality" out of the debate for a minute - there are just as many terrible ones on the Windows Phone platform...
I would agree that some apps I've used on Windows Phone are beautiful - they're good looking, better in functionality and ease of use than I've seen on the Android equiv (I'm only comparing apps available for both). Some are far worse - and the whole design of the Windows Phone UI (is it Metro? Is it "modern ui? Is it Windows 8 style, MS don't even know...) is a love it/hate it thing - sometimes I love it, sometimes it's a limitation.
I genuinely think windows Phone has some plus points - but it has a lot of negatives. The apps thing shouldn't be under-estimated because "Joe Public" (the type that doesn't read/post on this type of forum) DOES care - and if 500,000 are on one platform and 100,000 are on another, it does matter to them, and equally if the apps they most want are not on the platform, it's not a choice. It won't matter how good other aspects of Windows Phone is.
The phone design themselves, and apps are undoubtedly the biggest thing for the average user if the other aspects are in "acceptable" territory.