[ufukbay]

Some people and sometimes I catch myself doing it send a sentence in multiple messages since the message doesn't cost anything compared to a sms where you would definitely try to fit as many characters as possible into a single message.

However I'm not sure how common this is and if it could be one of the reasons for the high amount of messages per user.

[mcagl]

Yeah, sometimes it is used more in an "IRC" way than in a "SMS on steroids" way.

I think that the web and desktop clients just push this probability. Having a computer keyboard instead of a phone to write triggers a different "state of mind" in the user, I think. At least it's like that for me.