Something worthy of being written about on Twitter. It may be good or bad - it applies to anything worth a tweet.
"I'm loving the sunshine today. This weather is totally tweetable."

"Dude, I had the most tweetable burger for lunch yesterday."

"My package from Japan should arrive tomorrow. It's gonna be so tweetable."
by Lewis! August 17, 2009
Someone worthy of tweeting about because they are very interesting, funny, or cool. Someone tweetable is always quoted.
by trololcat June 23, 2011
The ability to consistently create important tweets without going over the top. Relaying the most important information of your day.
Joey: "Dude have you read Nick's tweets?"

Kevin: "Why?"

Joey: "They are too dank. He's got some major tweetability."
by graftonsoccer1021 March 6, 2011
She's got some mad tweetabilities right there; her tweets constantly fill my home page with new updates.
by tweeber January 19, 2010