Like Pittsburgh (population 310k, 55 square miles), Boston, Mass. (population 609k, 49 square miles) is trying to get more money from its tax exempt properties, especially those properties owned by the health care and university community.
Here's how some of the comparative data stacks up: Both cities have collected voluntary donations under PILOT (payment in lieu of taxes) payments for years. Recent data shows that Boston received about $13.3 million in PILOTs; Pittsburgh, during the recent years of Act 47 and the establishment of the Pittsburgh Public Service Fund, received contributions in the area of $14 million over the three year period of 2005-2007.
Keep this in mind that according to published reports and the Boston City Assessor's office that the value attributed to that City's health care and higher education institutions alone is $12.7 billion: by comparison Pittsburgh's total exempt value (non-profits, government, etc.) was $7.7 billion in 2008. Pittsburgh's taxable property value ($13.2 billion) is slightly higher valued than Boston's exempt property.
Boston wants to have a gradual movement toward having the non-profit community pay up to 25% of their assessed value in a PILOT to the city. Pittsburgh's recent approach was to propose a raft of fees, such as charging for water use and possibly hospital stays, before settling on the now dead tuition tax.
Both cities likely are quick to acknowledge that the non-profits deliver wonderful benefits but pay no taxes. It is also fair to say that it is likely that neither has conducted a study measuring all of the related costs and all of the related benefits from the non-profits to determine whether or not, on net, the city derives a loss or a benefit. Until that happens, the PILOT talk fails to achieve liftoff.