It's not twitter. It's not the excessive dumbing down in fiction or the grammar Nazis preventing new learners from getting better.
What's really killing this beautiful language is the British embassy itself. Don't believe me? Check out this text I received from them.
I mean just look at these strange typos and grammatical errors.
Regardless of that, am taking them up on their prize. Might even use it to open some schools that impart excellent education in English.