In Depth: Apple's Leopard leaps to new heights

Like the Finder's Sidebar, Mail's Sidebar has also received an iTunes-esque makeover and has been tidied up with categories for Mailboxes, Reminders, On My Mac, User's Mail and RSS feeds. Mailboxes store the usual In-box, Sent, Trash and Junk subfolders, while the On My Mac and User's Mail sections store local mailboxes and Smart Mailboxes.

The RSS section allows you to read Real Simple Syndication feeds using Mail's interface. RSS feeds can be added through File --> Add RSS Feeds, and Apple includes its own Hot News by default. Mail's newfound RSS ability is integrated with Safari as well, ensuring that feeds are always in sync and up to date. RSS feeds that have been read in Mail won't mistakenly appear unread in Safari.

Reminders is an entirely new section in the Mail Sidebar and offers a place for quick access to even more new features: Notes and To Dos. Notes is exactly what it sounds like: a quick and easy place to jot down notes, complete with the look of a yellow legal pad. Notes even syncs with other computers using .Mac, although it doesn't sync with Apple's Stickies app or the Dashboard Stickies widget. That's surprising, given the high level of integration Apple has built across its applications.

As for To Dos, they can be created from Notes or just by highlighting text and pressing the To Do button located by default in the Mail toolbar. Selecting the To Do section in the Sidebar shows the list of things you need to get done, and any listing can be edited via a contextual menu. To Dos can be assigned due dates, as well as alarms, and can integrate with any calendar in iCal.

It's easy to turn a note into a To Do task. (Click for larger view.)

This version of Mail allows you to archive mail directly from the Mailbox menu, allowing for easy backups of important messages -- and it reintroduces technology that hasn't been seen since before the Mac OS X days: Data Detectors.

Back in 1998, Apple described Data Detectors as "a new technology that enables your computer to recognize and act on certain types of information in your documents." Data Detectors were used to find things such as an address within an invitation, and they offered context-sensitive options such as the ability to look up the address or add it to your address book.

While Data Detectors were a useful, if little-known feature, the technology died a quiet death until its resurrection in Leopard. Data Detectors, now integrated in Mail, automatically recognize e-mail addresses, URLs, phone numbers and appointments when your cursor hovers over the text, letting you quickly create new contacts, make appointments or choose other context-sensitive options.

Expanded iChat

What started out as a simple instant messaging client with a cute interface has grown up to be a powerful yet intuitive conferencing application in Leopard. In what remains an Apple hallmark, iChat has gained extensive functionality while maintaining ease of use. Starting a text, voice or video conversation is still as easy as picking a buddy and clicking one of the corresponding buttons near your buddy's name.

This version, however, introduces a new button called Start Screen Sharing, which allows you to access another Leopard user's desktop -- once you get their permission, of course. While remote desktop applications have been around for a while, the genius of this feature lies in its implementation. IChat uses its Buddy List as a way to track user location, so you can connect to anyone across the world without having to worry about IP addresses or any complicated network configurations.

With iChat's screen-sharing capabilities, it is possible to remotely access another Mac running Leopard, with full drag-and-drop support. Apple's implementation is fairly slick, as both desktops are visible (running picture-in-picture view, no less) in a manner that allows for quick switching between the two. The animation illustrating the switching desktops is not only impressive and perhaps even fun, it's also useful, since it conveys exactly what is happening: One desktop is being switched by the other.

How about a chat in front of Yosemite waterfall? (Click for larger view.)

On the lighter side, iChat inherits Photo Booth's live effects, allowing you to choose from dozens of effects and apply them to your active video chats. One-upping Photo Booth, however, is iChat's new Backdrop Effects capability.

This nifty feature prompts you to move away from the camera's view so that the computer can "learn" the current background. After a moment, you step back into the frame, and the background is wiped out and replaced with whatever image or movie you select, either from Apple's samples or any you provide.