It's one of the 'thread-waisted' wasps, normally they would not be easy to identify as there are so many similar ones, some of which are yet to be recorded. Numbers of species goes into the many thousands.
However, I can see definite white marks on the side and bottom of the thorax which suggests Eremnophila aureonotata. I have no idea if there are any similar wasps, there often is but it looks a good bet.
http://bugguide.net/node/view/...
This type of wasp is very unlikely to attack humans, and if you see a long pointed thing on it's tail end it's likely to be the ovipositor of the female which is used to lay her eggs. They will be beneficial in that they use caterpillars as hosts for their offspring.
http://vimeo.com/19973205
It seems there is only one species of Eremnophila in eastern North America ..
Range. Eremnophila is primarily a Neotropical group. One species however occurs in eastern North America
http://www.discoverlife.org/mp...
