Windows Phone Thoughts: The Mobius Files: Will 'App Lock-In' Slow Adoption of Other Platforms?

I read an email on the Mobius list where the idea was that because consumers have already adopted the iPhone in droves, they won't be interested in Windows phone 7 came out. Here was my response (with some added thoughts).

Consumers are fickle creatures; they change their minds all the time when it comes to phone contract renewal time. HOWEVER...I wonder if "app lock-in" will play a role in moving to other platforms? As in, you're Joe Smith and you have an iPhone and you've spent $200 on apps over your two year contract...that app investment, will it make you feel like you need to stay with your iPhone even if there's another phone you like more? I wonder...

The reality is, of course, that the majority of users don't yet have smartphones - so in that sense the market is wide open - yet I think the biggest adoption blocker remains the costs of data plans. If you want your phone to do more than make calls, sent texts, and MMS, you're increasing the monthly outlay by a fair bit - especially if you're a light phone user with a small minutes plan, it can easily double the monthly cost of your phone bill (it does in my case). Until the carriers start to want all these people on their data networks, I think data plans will remain expensive, and the bulk of the population will stay away.