I'd say Buffet's pretty active considering the size he moves:
As of 10-05-07:
New positions: KMX, WBC
Added Positions: BNI, DJ, JNJ, UNH, USB, WFC
Reduced Positions: AMP, NSC, UNP
Sold Out: COV, FDC, PTR, TEL, TYC, WU
http://www.stockpickr.com/port/Warren-Buffett/