As of today, all Twitter users can have up to 280 characters instead of 140. The first limerick was written with the old limit, the second makes use of the new limit.
OLD
A 140-character tweet/
Is brief, to the point, short and sweet/
280/
May make them more w80/
But not quite so damnably neat.///
NEW
A one-forty-character tweet/
Is brief, to the point, short and sweet/
Two hundred and eighty/
May make them more weighty/
But not quite so damnably neat.///
😀