When I was at the October 16 Open Interview events, I met lots of other folks, and none were EA. They were all R1.
I think this website as a whole has seen increased activity from last year to this year, which explains the EA jump from 9 to 25.
The number of Round 1 candidates in the Rollcall will certainly increase with time (well beyond 50), especially over the next two months, just as EA rollcall has increased recently.
I think the release will be this Friday, as it was released on a Friday last year and the year before.
November 2009: It was released on Fri, Nov 20, instead of Tues, Nov 24
November 2008: It was released on Fri, Nov 14, on-schedule