oblig: s/affect/effect/
Still I think the 140 character limit was in part due to their continued success; I know when I look at a tweet, I'm not going to get a 1000-word dissertatino on a subject - I will get bite-size pieces of info (for the most part, except for the multi-part diatribes or conversations, which I generally ignore).
Link anxiety is a real thing - I'm less likely to click if it's going to absorb my attention for 5m+.