Been using the X10 with the MW600 for 3 months now.
-be synched to your laptop and when you receive a call, the phone will take over.
-listen to radio and answer calls.
-See the phone number of whomever is calling you.
-double press the talk button to redial last outgoing contact.
-Use the play, rewind and forward buttons to control mediascape.
-See the name of the contact even if it is saved in your phonebook.
-See the name of the track.
The two can'ts are what stands the mw600 out, but I honestly do not regret getting it as for it has decent audio transmission. Plus, there is a chance of this all being fixed after update by SE
HTC Magic -> HTC Hero -> Xperia X10 -> Nexus One -> SGS Vibrant i9000 -> Nexus S -> Xperia Arc -> SGSII i9100 -> Galaxy Nexus i9250
"Science knows no country, because knowledge belongs to humanity, and is the torch which illuminates the world."