Whoa, I thought they ran out of Big Cat names
My best guess in features.
1 - iMacs will have the Retina displays
2 - iMac and Apple displays will be touch screen active
3 - 10.7 will be fully touch input native. (screen wise)
4 - 10.7 will have face time this will push out iChat video
5 - 10.7 will have better syncing will all devices
6 - 10.7 will have the normal bug fixes and speed boost
7 - Hardware speed bumps all around
8 - New pro-tower design <-- long over due.