Albans/News Curtis Sliwa (above) leaves WABC on Monday and will be replaced by John Batchelor seven days a week. Whether you think Curtis Sliwa is a street-smart good guy or one of local media's all-time great self-promoters, WABC (770 AM) won't sound quite the same without him. John Batchelor, who moves into Sliwa's old 9 p.m.-1 a.m. slot starting Monday night, likes to have fun and play music. But he also takes a methodical, scholarly approach to international geopolitics, often with an emphasis on the Middle East. Compared to Sliwa, he sounds downright professorial. Having Batchelor in the late-evening...