Nice one. Since I bought my new MBA 11.6" two months ago with Lion pre-installed, the OS has frozen on me three times - all three requiring a reboot (couldn't even force quit the finder - the keyboard and trackpad locked up).
This has been in addition to a number of prevailing bugs, such as windows not responding, getting stuck behind each other, hanging, generic icons, Launch Pad reshuffling all my applications at random and trackpad issues (which may have more to do with the machine itself than Lion).
I've got Snow Leopard on an MBA 13.3", Leopard on a MBP 15" and Tiger on an old G4 iMac - can't remember the last time when any of those machines/OS's froze on me or displayed similar behaviour to the examples above.
Sorry, but to some of us Lion's issues are no joke.