there are lots of problems with existing GPS devices connected to Windows:

1. as these devices are (not all but mostly) using NMEA proprietary format to provide information, apps need to pay for NMEA and know its different implementations which leads to increasing costs of dev/support/licensing

Windows Location Platform gives free open APIs standard for all APIs eliminating need for end-apps to know NMEA and lots of it implementations

2. as these devices are connected via COM, only one app can use location data at one time

Windows Location Platform enables concurrent access to several apps at the same time

3. for now, only GPS devices are widely used, without GPS location-aware apps do not work

in Windows Location Platform we have support for different location sensors (read providers):
GPS
IP Geo Location
Wi Fi Triangulation
Cell Tower Triangulation
and virtually any new kind of a location provider

and if you do not happen to have any of the below solutions, you can still use “Default Location Provider” which enables user to enter his location into one place where it will be then used by every app

I think these arguments are enough to understand why Location Platform is an innovation for Windows versus just NMEA-custom implemented devices.

http://franson.com/forum/topic.asp?TOPIC_ID=3968

Also more relevantly on topic I once read about a guy at Microsoft who had his email and computer tied to his presence. It would monitor his keyboard, webcam and microphone and if he was away for a set period of time it would auto reply back to emails or forward them to his cell or even give a reply with his cell phone number if it was someone he replied back to a lot (looked at frequency) this is just one of the many things i imagine these api’s would be good for.