WOWT will offer viewers of its 10 p.m. newscast six chances to win tickets to Paul McCartney's Qwest Center Omaha Concerts in October. Not coincidentally, the giveaway will take place during the first week of the May sweeps period. Channel 6's ratings have slipped over the past several books, and the hope appears to be that spreading out a McCartney ticket giveaway over seven days between May 1st