Microsoft has announced a new set of technologies aimed at integrating phones and the computer, code named Echoes.
This is still a couple of years away, but looks like they plan to more closely integrate Live and the mobile phone etc.
There is already a service called GrandCentral, which was taken over by Google around 10 months back. GC actually provides you with 1 phone number that can be mapped to your other phone numbers and it will forward calls accordingly. Also it would record voicemails and then send a link to you via email so that you can check your voicemail from your computer.
Though Echoes does seems to integrate this and the IM and other stuff, I dont see it as something revolutionary, atleast based on the information available.