SocketAsyncEventArgs should be returned to pool per call

[loudej]

Could use less memory if you don't have 2 of those overlapped managers allocated per active connection... They only need to be taken from pool for the duration of an async call. Essentially the same places where the Completed delegate is assigned would be where you would acquire and free the object.

[loudej]

Before this is done - of course - the memory pool should actually pool these.