My home phone on SP1 using GV blinks there is voice mail and does the double tone thing saying there is VM where there isn't. I call GV voice mail and it says no new messages but the phone is blinking, VM it lit up and double tone.
I get email notificaiton on missed calls, voice mails ect ok - just the phone says there is VM when there is or isn't.
Not a huge deal - but annoying.