Miles & More is Lufthansa's frequent flyer programme - as Lufthansa is in the process of buying bmi, many members feel that Diamond Club will be assilmilated by M&M.
Other here, myself included, feel that DC will survice in its own right, even if changed considerably.
Either way, we mostly all feel that the buying power of DC miles will diminish - which is a shameful way to treat people who have built up loyalty points...