I’ve been running Lion on my laptop since the GM came out in early June, and on my iMac since the official release. Some folks are still holding off on upgrading. Unless you’ve got some mission-critical piece of software that is incompatible, I see no reason to. It’s better in pretty much every way.
Lion is clearly optimized for the trackpad. Enough so that, if you use a mouse, I would suggest ditching it for the Magic Trackpad. I did this even before Lion, but Lion makes it all the more worthwhile. I don’t miss a mouse at all.
Aside from the under-the-hood advantages and various modernization upgrades, the biggest advantages of Lion for me are:
- Mission Control: I’ve been hugely surprised how much of a difference this makes. A three-finger upswipe now reveals all your spaces and windows, neatly organized. Unlike the random disarray of Expose, which I always found clunky, Mission Control makes it incredibly fast to find what you are looking for.
- Trackpad Gestures: iOS gave Apple a great deal of experience with developing a gesture-based UI. While the Lion experience is a bit less direct because of the lack of a touchscreen, with a bit of effort the touchpad adds another dimension of control over what was possible with the mouse. If you’re used to the old-style trackpad scrolling, Lion is disorienting at first as it reverses the direction of scrolling, but it really does make more sense with the trackpad, as you feel you’re directly manipulating the page as opposed to the scrollbars. Swiping between spaces, between pages in Safari, and adding pinching and zooming capabilities to web pages enhance the experience considerably.
- New Mail App: Better layout, better organization, better searching. Just better. The best addition: a browser like favorites bar. Navigate to folders by pressing command-1, command-2, etc. Move messages to the same folders with command-control-1, etc.
- Full disk encryption: I was a prior File Vault user in Snow Leopard, but this essentially made your entire home directory an encrypted disk image: one huge file that was mounted as a disk each time you logged in. This meant that anything outside of your home directory was unencrypted, but a bigger issue was that it rendered Time Machine (one of the best features of the Mac OS) useless, since any minor change would mean backing up a huge monolithic home directory file. Forget about tracking the history of a single file: it was impossible.
There are many other new features in Lion, some of which (e.g. versions) have a lot of promise that is yet to be realized because of application support.