Via Ambinder, the Des Moines Register is reporting that Iowa's parties have agreed to hold their 2010 (that's 2010, not 2012) caucuses on a Saturday afternoon, instead of the traditional Monday evening. They may go with a Saturday in 2012, or not. We'll see.
This is one of those things that is apt to be massively overanalyzed and make zero difference. Ambinder says that this comes in part by Hillary Clinton supporters who are convinced that the turnout of the caucuses skewed against her candidacy, but even to the extent that might have been true there's no reason to expect a similar division or effect in the next contested Democratic nomination, which presumably will be in 2016 and will involve none of Clinton, Obama, or John Edwards.
The bottom line is that caucuses yield very, very, small turnouts, and jiggering with the conditions isn't going to change that.