No, people making over $250,000 can still take charitable write offs. It just changes the amount they can take. It's really not that much:
The Obama plan would cap the value of deductions for families making $250,000 and up. Under current law, a $1,000 deduction is worth up to $350 for such taxpayers, because they can avoid tax rates of up to 35% on that income. The Obama cap on deductions would make the $1,000 deduction worth a maximum of $280.
An $80 decrease per $1,000. I think they can handle it.