Standard&Poor's Ratings Services assigned its 'A+' standard long-term rating, and stable outlook, to Austin, Texas', doing business as Austin Energy, series 2008 taxable electric utility system revenue refunding bonds and affirmed its 'A+' standard long-term rating and Standard&Poor's underlying rating (SPUR), with a stable outlook, on Austin's separate-lien electric system revenue refunding bonds. The ratings reflect the electric system's: Diversified generation resource mix that consists of coal and efficient nuclear for base load, with the addition of a combined cycle unit in 2004 that allowed the city to subsequently retire older, less-efficient units -- the last of which was retired in 2007; Competitive rates with a separate cost-recovery component that allows Austin Energy to true-up for