Mortgage Interest Deduction reform

An interesting blog by Kevin Drum on the mortgage interest deduction.  Apparently this homeownership subsidy disproprotionately benefit high-income households.  Low-income households generally don't own, while middle-class households don't have mortgages that big.  But high-income households generally are homeowners and they benefit greatly from the mortgage interest deduction.

This begs the question, of course-why do we have it at all?  If high-income generally are homeowners, do they really need this deduction as an incentive to purchase a home?

That doesn't mean people are suggesting we eliminate it entirely (OK, maybe some are), but suggestions range from replacing it with a tax credit to capping the home price to limit the deduction.