They are referred to as "stickies". Some are the ed's own questions; others are questions from the likes of you and me (well never me actually) which the ED deems to be good questions which should be given top billing.
Yes I know I've not entered into the spirit of CB by giving a witty answer. My last attempt at humour brought me a stern ticking off from the Ed today so i'm playing it safe
Oops sorry, mollykins- Spare Ed and I may appear to have hijacked your thread. Hope we don't both get a ticking off from the main Ed when he comes back on.
Anyway I think your question has been answered fully now.