That deceptive baseline makes all the difference in the world; take it away, and what you have is Obama reducing the deficit from recession-era highs created by TARP and the stimulus package - which are both designed to be temporary anyway - to recovery-era lows that are no lower, as a percentage of GDP, than the deficits Bush ran during his administration's years of economic growth.
This is misleading. Now, it's true that Obama does not project the deficit to fall lower than it did under Bush's best years. But this is because the deficit is projected to rise under current policy. If we kept all current policies in place, and enacted none of the changes that Obama proposes, then the budget would run an average deficit of 4.9% of GDP over the next decade -- 4.4% of GDP in 2019.* With all the changes Obama proposes, the cumulative deficit over that decade will be 3.9% of GDP -- a full percentage point lower -- and 3.1% of GDP in 2019.
So the point is clear: compared with current policy, Obama would reduce the deficit. If none of Obama's changes were enacted, the deficit would be higher. Now, it's true that Obama's changes make the deficit higher in 2009 -- appropriately, I say -- but even so they make the deficit lower over the whole course of the decade. Like I've said, does this go as far as I would like it to in an ideal world? No. But is it fair to compare Obama (who makes the fiscal outlook somewhat better) with Bush (who made it dramatically worse)? Of course not.
*The only arguably misleading thing about this baseline is that it assumes we would continue the same presence in Iraq over that time, which might have happened if Republicans kept control of the White House but could very well not. But even if you bent over backward and assumed that Obama's Iraq policies will produce zero savings, it doesn't change the bottom line fact that his budget saves money compared with current policy.