Election Data Services is predicting the impact of the 2010 census on Congressional Redistricting, as summarized here. A few results are close and depend on hard to predict 2008-2010 population trend nuances.
Florida +1 to +2
North Carolina 0 to +1
South Carolina 0 to +1
New York -2
New Jersey -1
Minnesota 0 to -1
California 0 to -1
In short, bad news for blue states and good news for red states, in the Presidential race. Impact on Congressional races depends upon how redistricting plays out. The gains in red states are often in the more liberal parts of those states.
Colorado will neither gain or lose seats as a result of the 2010 census, but redistricting may still change the balance of power in the state towards areas that are gaining in population and away from those that are losing population.
Gains in the conservative Southern suburbs of Denver will help Republicans. Losses in rural farm country will hurt them.