I have Windows 7, so things may be different for you. I won't even use apps from small developers, because those can become abandonware on any platform.
-Take Angry Birds Star Wars. How many updates since it was released? NONE!!! EVER!!
Android and iOS have 300-400% more levels which were added with updates.
- Look into Pocket Gods. Not being updated AT ALL. Again Android and iOS have vastly more levels. At least 200% more, but probably in the 300-400% more range as well.
I could go on and on. Simply put many apps NEVER get updated. To add insult to injury they cost more money. You can buy 3 Android apps for the cost of 1 Windows app. The app marketplace is a huge reason MS is not getting decent marketshare.
Say what you want about BlackBerry, but they were smart to guarantee $10,000 to anyone who gets their app accepted into their marketplace. They will be launching BB 10 with a more impressive app store than Windows app store which had a 2 year head start.
With Microsoft's deep pockets they could even do one better and give developers a 1,000 to 2,000 dollars upfront so they can afford to spend time working on it. For the cost of a television commercial to be aired a few times they could have a whole army of people making apps for them. It seems like a no-brainer to me.