Apparently, large parts of the American federal budget will be subjected to a budget freeze for three years in the President's upcoming 2011 budget proposal. Word on the street is that NASA as a whole will get a slight increase, but my betting is that any increase will go to manned spaceflight and Earth science missions.
In a week we'll know what the proposed budget will be for NASA's planetary program. In the meantime, I did a little work with Excel to see what a budget freeze in the planetary program would mean. Typically, inflation runs at around 3% in a year. Consumer inflation in 2009 was 2.7%; I don't know what the inflation rate was for aerospace spending and will use 3% as a guideline. If the planetary program were subjected to a three year budget freeze and then budgets rose to cover inflation, the loss of spending power would be a fall between the burdened costs of a Discovery and a New Frontiers mission (~$950M FY09 dollars). If the budget freeze were extended over an entire decade, the loss of spending power would be equivalent to a Discovery and a New Frontiers mission (~$1.8B).