At this time JULY 9 2010 no one knows what the income tax rate
will be for the tax year 2011 when you file the 2011 tax year
income tax return in the year 2012.
And there is not expected to be a tax rate on "salary income"
and never has been. Tax is paid on either taxable income - which is
different than "salary" by many factors, including acceptable
deductions and exemptions, and many other things, with a different
rate applied only to certain Long Term Capital Gains or entirely
exempt income.
It would be uncommon for 2 people, even working the same job
with identical salaries, to pay the same tax.