Interesting facts about preferred shares from Wikipedia:

United States

In the United States, the issuance of publicly listed preferred stock is generally limited to financial institutions, REITs and public utilities. Because in the U.S. dividends on preferred stock are not tax-deductible at the corporate level (in contrast to interest expense), the effective cost of capital raised by preferred stock is 35 percent greater than issuing the equivalent amount of debt at the same interest rate. This has led to the development of TRuPS: debt instruments with the same properties as preferred stock. With the passage of the Dodd-Frank Wall Street Reform and Consumer Protection Act in 2010, TRuPS will be phased out as a vehicle for raising Tier 1 capital by bank holding companies. Outstanding TRuPS issues will be phased out completely by 2015.[13]

However, with a qualified dividend tax of 15 percent (compared to a top ordinary marginal tax rate of 35 percent),[14] $1 of dividend income taxed at this rate provides the same after-tax income as approximately $1.30 in interest. The size of the preferred stock market in the United States has been estimated as $100 billion (as of early 2008), compared to $9.5 trillion for equities and US$4.0 trillion for bonds.[15]