Yes, there are sites that arrange the financial information for the charities, or rank them according to their efficiency (like CharityNavigator). But as you correctly mentioned, this is based on the data, that the charities submit to IRS, which can be subject to any creative accounting..
Real time can put some pressure at first, but when transparency is accepted as a public standard, the organizations should get used to be accountable for their actions.. We'll see where it goes )