The initial reaction to the three year discretionary non-defense spending freeze that Barack Obama is proposing, is that this is not the time. In the middle of a deep recession is no when you want to be cutting government spending.
For one thing, it's a very small percentage of the budget. It's supposed to save $250 billion over ten years, with the bulk of those savings coming in the out years, since the freeze is not indexed to inflation. That's trivial in light of an accumulated deficit of trillions over the same time period.
But even then, it's not likely to work. Congress has to make this happen, and though there is a lot of wasteful government spending, virtually all of it comes attached to some motivated interest group with at least one congressman in its pocket. Moreover, this freeze is supposed to happen in an election year, when Congressman want to ship as much pork as possible to their constituents. Come to that, Obama may not be so enthusiastic about it if his poll numbers aren't good.
We're going to get spending cuts when there is bipartisan consensus that they have to happen--and more importantly, what cuts should be made. Things like base-closing commissions work because there's consensus about what should be done, and congressmen just need political cover to do this. But there are deep, deep divides over taxes versus spending cuts, welfare versus defense, and so forth. Maybe if everyone's sufficiently battered by the next election cycle--and the bond markets--we'll get some real action. Until then, this is Obama's mouth writing checks that his legislature can't cash.
Update: I was apparently in error about 2012; ABC says it starts in 2011. I move the dial back to "harmful".