Air Drop Between Lion and Mountain Lion?

I don't have two systems to try it on, but there is no reason it shouldn't work. AirDrop is just an ad-hoc network connection setup between the other computers on the network.

I've actually tried this and I keep getting a "transferred cancelled" message even though I never cancelled the transfer nor did I receive a prompt requesting authorization to transfer the file on the Mountain Lion computer

I can confirm it works, using an iMac running 10.7.3, and a MacBook Air running 10.8. Had no issues, worked just as though both machines were on 10.7

Wirelessly posted (iPhone 4s: Mozilla/5.0 (iPhone; CPU iPhone OS 5_0_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9A405 Safari/7534.48.3)

As above it works fine for me too!

when I click AirDrop I get a blank screen.... On the other MBP with Lion I can see my computer though