It's Cameron
By 134,446 to 64,398, or 67.6% to 32.4% of the vote, on a turnout of 78.4% or 198,844.This is a bit less than IDS got in numbers (155,983) but turnout then was higher than the total electorate now, IDS's % was only 60%.
Update: If you take the number of days Thatcher, Major, Hague, IDS and Howard were in office (up to when they said they were standing down or stood down) you get a very nice fit on a curve, which suggests that Cameron will last 329 days. Thus he will be standing down on the 31st October 2006, presumably after a bad party conference. If he doesn't then he is a breaking a law of nature, and clearly should resign.