The new email client in Tiger is… frustrating, but promising.

Thumbs down for the lack of keyboard accelerators, the weird toolbar icons (which totally violate Apple’s own UI guidelines), the pale blue folder panel, and the funky animation when you choose a message from a set of search results.

Thumbs up for “Smart Folders”, and the way they interact with the rules-based filing and filtering. A smart folder is like the smart playlists in iTunes: the contents of the folder are defined by an arbitrarily complex predicate.

I’ve defined two smart folders: ALL-UNREAD, and UNREAD-4-ME. (I’d like to colour-code them, but no….) The ALL-UNREAD folder contains all unread messages. UNREAD-4-ME contains those unread messages in which "Any recipient" contains "geoff". (I wanted to define it based on the "To:" header only, but no….)

For example: when a new message arrives from my boss, Samir, addressed to me, my rules cause it to be filed in the folder "Active/G2". The unread count for that folder is displayed in the folder panel. In addition, the message satisfies the criteria for both of my smart folders, so it will show up in both of them. Of course, as soon as I read the message it will disappear from those smart folders. On the other hand, the unending stream of messages on the "mac-users" and "solx86-interest" aliases will be filed away and will only show up in the ALL-UNREAD folder.

The bottom line is that this lets me see at a glance how many new messages are addressed to me, and how many I’m getting by virtue of list membership. If I’m in a hurry, I can simply scan the UNREAD-4-ME folder, and I can do this using just the space bar and delete key.