People who use the microblogging service Twitter(noun)
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Use "twitterati" in a sentence
"Twitter works great for the "twitterati," but in many ways it has failed to penetrate the mainstream web."
"I've been on for a few weeks now and have just found it nearly impossible to break into what is, despite superficial appearances, quite self-contained to a group of "twitterati""
"By lunchtime Thursday I had published a bunch of qik videos and pix from #cebit and met many of Sydney's finest 'twitterati'."