I did the southern-most blocks of East Harlem today, walking E. 109th St. through E 97th St. (about 10 miles). I've now done almost 100 blocks of contiguous streets (from 60th - 155th). That isn't quite as impressive when you consider how much space Central park takes up in those blocks, but it's progress.
I've written more about "Regular Harlem" than I have East Harlem (also known as Spanish Harlem or "El Barrio"), which has a much different character. Ethnically, it's largely Puerto Rican and economically it's depressed. The area has the highest rate of unemployment in New York and the highest concentration of public housing in the US (just behind Brownsville in Brooklyn).