From the Hacker News thread
I don't usually quote pg, but I think in this case it's relevant: "Old Twitter is what you'd get if an engineer brought New Twitter to Steve Jobs, and Steve beat on him relentlessly to simplify it." (twitter.com/#!/paulg/status/25998745559) To me adding a file upload button, a To:/CC: field, a link field, etc. etc. would be even worse. The beauty of an API is that power users can download and/or signup for apps that add on to the original service in the exact, fussy way they want. And non-power users can just type into a textarea.