A person who obsessively Twitters--that is, writes what they are doing every moment.
Person 1: Hey dude, what's up?
Person 2 (frantically): I have to Twitter this! You just asked me what was up! *Twitters that Person 1 just asked what was up.*
Person 1: Um, sure. I, um...have to go now. Bye! *innocently grins*
Person 2: *frantically Twitters that Person 1 is leaving*
Person 1: Wow, you're such a Twitterbug!
An Individual who is a frequent spammer in the space. Think of them as the online litter bug. Particularly on Twitter, this person will spam daily, posting irrelevant tweets, resulting in a major cluster of useless information. End result, could potentially drive innocent tweeters to delete their accounts out of frustration. Against their will, this person may be classified as a Twitter Quitter.
Sherman: "Hey man, I don't know about you, but I'm really getting sick of Burnedette's tweets"
Dwight: "Oh yea, Burnedette is a total Twitter Bug.."
Someone who spends a great deal of their time on micro blogging service, Twitter.
“Why are you spending so much of your time on Twitter? If you’re not careful, you’ll turn into a Twitterbug.”