CBOT Fed Watch

Though it surprises me that it is not weighted more heavily toward a cut of .25%, it would be safe to say the market is split over whether the Fed will cut rates by .25% or .50%:

CME Group Fed Watch – September 17, 2007: ...Based upon the September 17 market close, the 30-Day Federal Funds futures contract for the October 2007 expiration is currently pricing in a 100 percent probability that the FOMC will decrease the target rate by at least 25 basis points from 5-1/4 percent to 5 percent at tomorrow’s FOMC meeting.

In addition, the 30-Day Federal Funds futures contract is pricing in a 50 percent probability of a further 25-basis point decrease in the target rate to 4-3/4 percent (versus a 50 percent probability of just a 25-basis point rate decrease).

Summary Table
September 11: 28% for -25 bps versus 72% for -50 bps.
September 12: 26% for -25 bps versus 74% for -50 bps.
September 13: 42% for -25 bps versus 58% for -50 bps.
September 14: 42% for -25 bps versus 58% for -50 bps.
September 17: 50% for -25 bps versus 50% for -50 bps.
September 18: FOMC decision on federal funds target rate.

From the Cleveland Fed: