I love twitter, will tolerate facebook, and have had a spin on pretty much every messaging system with more than 5 users, wiki comments, IRC, plaxo, IM, whatever. I’m getting a bit bored by every financial reporter that wants to prove he’s hip discovering twitter and telling me email is dead.
Sorry, dude, email rules. Try to find the FB message you send your lawyer with your response to last years’ contract. Try to escalate the support request you tweeted to the technician’s manager.
Email gives me messages up to 10MB, archiving, search, lists, security, as well as mundane features such as spell checking and formatted text. Give me a call when FB / twitter ticks half of those.

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Yishay Mor, Researcher, London Knowledge Lab