Here's the details from the Nokia Conversations blog:
"Another slick game announced from Nokia here at CES, and it’s a part of the growing Bounce series. “Bounce Boing Battle” pits two players against each other using two separate Nokia devices (S60 v5 handsets). In a similar fashion as the classic “Pong”, opponents bounce a ball back and forth in an attempt to get it past one another’s goal.
As the ball approaches your side of the court, use your Nokia’s touch capabilities to draw a line in front of the ball. If you draw the line at the correct time at the correct spot, the ball flings back at an angle depending on the direction of your line."
Here's the video trailer from YouTube:
Screenshots (from Nokia Conversations):