Greenpoint’s East River waterfront is shaping up to be the city’s next vibrant waterside locale. Just last week we reported the sale launches of two new condo buildings (50 Greenpoint Ave.and170-174 West St.) near the low-key neighborhood’s shoreline. Now we can announce the topping-off of its first and tallest tower, fittingly namedThe Greenpoint. Inside the block-long development will be 95 condos and 287 rental apartments, most of which are to feature sweeping views of the river and Manhattan skyline.