atherthanradicallyexpandingtheallowablenumberofactualcharactersineachtweet,thevir-tuallimitoncharacterswasbeingexpandedbyallowingimagesandothermediatobeembeddedwithoutcountingtowardthecharacterlimit.
I'd say one of the most requested changes to Twitter (that I am aware of) would be expanding the character limit and adding an edit button