NEW YORK (Standard&Poor's) Aug. 31, 2011--Standard&Poor's Ratings Services said today that it has assigned its 'BBB+' issue-level rating to Norfolk Southern Corp.'s new senior unsecured notes due 2041. On Aug. 26, 2011, the company announced an offer to exchange certain debt securities. The proposed new note issue will not exceed $600 million. The final size of the notes offering is pending the results of the exchange offer. The ratings on Norfolk, Va.-based Norfolk Southern reflect its solid competitive position as one of the two large eastern freight railroads, its strong liquidity position, and the favorable industry risk characteristics of the U.S. freight railroad industry. Price competition from other railroads and trucking companies and the capital intensity