Don't take all the negative stuff so seriously. It's the Internet after all. You can find negative comments about kittens, rainbows, and Mother Teresa on the Internet. There are probably websites dedicated to bashing each of those things. If you own a 920 then you know that the build quality doesn't suck. It's arguably the best built phone on the market right now. You also know that Nokia has created a solid product so there is no need for Nokia to die (they are profitable again as of their last earnings report).
WP is just getting started and while MS doesn't beat their chest like some other companies, it's clear to me that they are committed to the WP platform. Do you think they revamped the iconic start menu UI in Windows 8, Windows Server 2012, and Xbox 360 to match WP live tiles just to throw WP away a year or two down the road? Do you think they made the effort to bridge the gap (tablets) in their ecosystem between the desktop/Laptop and WP just to drop WP and create a new gap at a later time? WP may still be lacking some apps and it may have a few rough edges (still smooth compared to android), but make no mistake about it, MS is committed.
I honestly believe that MS has the best overall ecosystem available at the moment and that by this time next year the WP platform is going to be in a much better position. Having said that, I'm very happy with the platform as it stands now and I enjoy being involved with something that is different and innovative.