"Webs may cancel skeins due to slipping ratings" Another Jackson trial, a visit from "Desperate" housewife Teri Hatcher and a truly gory report on faith healer John of God were among the offerings on ABC's "Primetime Live" this season -- under normal circumstances, a lineup that could be expected to bring big ratings. But "Primetime," once a top 10 hit, is down a whopping 22% from its so-so performance last year, despite a much-hyped revamp and the rising fortunes of the Alphabet webAlphabet web. Friday-night staple "20/20," in its first season sans Barbara Walters, is also down double digits. Newsmag...