Seems like it may be a Chinese Dogwood:

http://www.usna.usda.gov/Gardens/faqs/dogwoodfaq2.html
(there's a picture)

From that website:
Can I eat the red fruits of dogwoods?
Some dogwoods produce larger fruits than others, and some are tasty and some are not. The fruits of our native flowering dogwood, Cornus florida, are not poisonous, but they do not have a very pleasing flavor. The Chinese dogwood, Cornus kousa, has spherical fruits about the size of a quarter. When ripe in midsummer, they turn coral red and develop their full flavor and sweetness, with a flavor comparable to some melons. The cornelian cherry, Cornus mas, produces a tart, elongated fruit with a hard pit in the middle and a thin layer of flesh. These bright red fruits are sometimes used to make preserves, jam, or jelly with a flavor similar to cherries.