What's your favorite new feature in Lion

[ideal.dreams]

Everything. Love the full screen apps, the renovations to iCal/Mail, the new scrolling, the update to Safari.

 

[Infrared]

When I right-click on an App and choose "Show Package Contents"
it opens within the same window. I always used to hate how it would
open a new window. So, a small change, but a nice one.

 

[AlexH]

Mine is File Vault 2. Ive been envious of True Crypt and Bitlocker for Windows because of the full disk encryption that it does, now we have the same benefit in 10.7.

Me too! I feel safer dragging my MacBook Pro to work everyday knowing it is encrypted.

 

[Ronnoco]

Fullscreen apps (I use a 27" ACD with my 15" i5 MBP) with Magic Mouse and Airdrop to share files very quickly with my 11" MBA. I also really like the new Mail app and it's "Quickview" for links. Very useful for me...

 

[cuestakid]

full screen apps, launchpad, mission control and Improved full disk encryption.

 

[tblrsa]

FileVault 2, Full ASLR, Sandboxing