Standard & Poor's (www.standardandpoors.com) has revised its outlook for the debt ratings of Allied Waste Industries (NYSE: AW) (www.alliedwaste.com) to "positive" from "stable," signaling that the company has a better change of upgrades over the next two years. That upgrade could in turn lower its borrowing costs. The company reaffirmed its BB corporate credit rating, the second-highest junk level.