How much does your current ecosystem influence your device buying decisions?

I think the idea of a single unified theme across a bunch of devices (mobile, laptop, tablet etc) on the same platform is pretty appealing. I don't know how seamless syncing data between them is, but the companies certainly make it look very easy.

This interests me because (logically?) with so many Windows PC users, I would have expected more people to switch to Windows Phone (though I get that this is probably more to do with the relative youth and limitations of Windows Phone).

What do you guys think? Does what computer OS you use inform your phone and tablet or even games console buying decisions?

If there is anyone who is entirely invested in the Windows ecosystem (laptop, phone, xbox, Hotmail) are there any aspects that you find lacking?

Personally, I have a Windows laptop and a Blackberry, but if there was ever a Windows 8 phone with a hardware keyboard, I'd move over in a heartbeat.