Need more apps, need more apps, need more apps.
Sounds repetitive and stupid? may be, but there are apps i still don't see on WP that i use every day on android or iOS, and i don't even use that many apps!!
Springpad has no official app, neither do some of the local and ethnic developers. No official google apps except for search. No local Canadian weather apps like Degrees with push notifications (theweathernetwork is a joke even on iOS and android), no pushbullet app.
Doesn't sound like a lot of apps, but i use those almost every day. Feedly is a non-issue as pheeb and phonly look like decent clients, but many others have poor clients with missing functionality and official apps would be far better.
Not everyone uses just facebook, instagram, and angry birds.
Heck i couldn't recommend a lumia to my mother once her contract was up as some of the apps she uses on her iPhone do not exist yet. This is major fail.
Once the apps situation is worked out, windows phone will be just as tempting as android or iOS. MSFT needs to give loads of money or do loads of marketing for windows phone, or something else, but they need those apps on board. I would LOVE a lumia 920 or 1020 if those apps were available.