I am sure most of us have been waiting for the notification which was expected in first week of december but i guess due to some internal changes this is delayed.. Many are of the opinion that the delay is due to a change in the syllabi and a shift over to aptitude but this can't be confirmed as of now.. Many even speculate the notification to come in January, which i believe will mean burden on many aspirants for the paucity of time.. Under most acceptable circumstances i believe that the notification might come out sooner than later..
With regard to change in the pattern, probably only Mr. Agarwal knows about it.. Even closely placed sources with UPSC have not much of an idea on this aspect; so i belive we must not waste time and start at least GS prep for the prelims..