After reading Sheila Webber's post about What Librarians think about Second Life, I can't resist mentioning a rather mischievous post I was reading this morning about Twitter and Second Life by Chris Abraham "Twitter Is What Second Life Wasn't: Light, Cheap and Open And That's Why It'll Outlive the Hype Cycle". (I hope she will forgive me!)
He starts with admitting there's a lot of hype about Twitter at the moment and this may be reminiscent how it was with Second Life. But it's different
"Twitter is light, cheap, open and permanent, whereas Second Life is heavy, expensive, closed and ephemeral. Twitter does things right where Second Life failed."
There's some discussion at the end and I guess it's not a fair comparison, but it's a good read.