WBUR 90.9 has taken a big, early lead in the news-radio battle of WBUR and WGBH, reports the Boston Herald. Arbiton said it scored a 4.8 share of Boston listeners in January, 4.5 in February, 4.1 in March and 4.5 in April. WGBH, meanwhile, drew a 1.0 in January, 1.2 in February, 1.5 in March and 1.0 in April. WBUR is 11th in the market; WGBH, 23rd. The rivalry began last Dec. 1 when WGBH shifted its classical music programming to WCRB 99.5 FM and adopted a news/talk-dominated format for WGBH 89.7 (Current, Dec. 14, 2009).