Advanced rollover

http://www.wimbledonmovie.com/
Upon entering the site, check out the rollovers on the tennis balls…dope.
Anyone got any ideas on this?
I’m thinking the ball is just a tween to make it seem squished, as it triggers a movieclip like the falling snow tut on here. Except the hearts go upward, and dissappear at a certain y location. I’m looking to make something similar, I just want to start out on the right path. What do you guys think?