Its user base will never hit the 1.5 million units Microsoft claims are already delivered on its current trend, so somebody's about to get stuck with some dead inventory.
Microsoft gave every one of it's employees a W7 phone, but refused to give any to mobile developers.
There's no reason to develop apps for a phone with few users and no long-term prospects either.
What's worse is that developers are treated as second class citizens who don't have as much access to the hardware as "1st tier partners" do. And Microsoft doesn't give out all of the tools for free to developers like all of the other platforms. Microsoft will give out crippleware versions of the phone development toolchain.
The integrated WP7 phone Facebook app has a little over 300,000 users now and less than 4,000 Facebook likes. It looks like buying Facebook likes has gone out of vogue with Microsoft's marketing department.
The MS marketing department has a hell of a tough job. The biggest draw for facebook likes is to run a giveaway with ipads.