For comparison sake though, here are the current (2008) rates for married filing jointly:

$0 - 16,050:  10%
$16,050 - 65,100:  15%
$65,100 - 131,450:  25%
$131,450 - 200,300:  28%
$200,300 - 357,700:  33%
$357,700 - above:  35%

Dropping the top rate from 35% to 25% will never fly with the liberal, punish-the-evil-rich crowd.  It would do great things for the economy.  How it would directly affect the middle and lower class would depend on how deductions and exemptions are changed (if at all).