Yup. I care what you think :: 1.6 billion IM sessions per month are over 30 minutes

Awesome post on the Inside Windows Live blog – a must read.

Some statistics:

The average length of a Messenger session (a conversation) is 9-11 minutes
About 59% of sessions are over 5 minutes, with about 10% over 20 minutes long
1.6 billion sessions per month are over 30 minutes long
People use Messenger to exchange over 380 million photos a month —over 4.5 billion photos a year (this is in addition to the tens of billions of photos people also share each month via Windows Live SkyDrive and Hotmail)
Messenger users have 230 million voice & video conversations per month
Average voice session length is about 18.2 minutes
Average video session length is about 13.3 minutes
9% of video calls and 13% of voice calls are longer than 1 hour
Usage of international voice and video sessions differ geographically.
Brazilians use voice & video only 13% of the time for international connections while users in other countries, such as Spain or Germany, use voice and video 50-75% of the time for long distance chats with friends and family.