This is the conclusion of researchers from Binghamton University. Scientists have proved that point at the end of the message perceived by the interlocutor as a lack of sincerity in the words. Just experiment was attended by 126 volunteers. They were asked to read someone else's text messages and handwritten notes, says The Hindustan Times.
Correspondence in the network were minor in nature and consistent with daily communication. The presence at the end of each message point, established researchers, making communication less sincere. At least so thought the volunteers who consented to the study.
Apparently, punctuation and thorough enforcement of the rules isn't needed with online communication. Much more then the speed of typing, emoticons, and acronyms.