Among the various interesting keynote presentations at the Web 2.0 Expo earlier this week was one by IBM mobile computing researcher Jeff Pierce.Pierce observed that mobile e-mail clients have been designed just like desktop e-mail clients but that mobile e-mail clients are used quite differently.

Going through e-mail on a mobile device turns out to involve a lot of message triage, replying only to critical messages, deleting messages, and deferring other replies until back at the office or home, where there's a computer better suited to considered composition, research, and editing.

Mobile e-mail users also turn out to be adept at identifying messages just from the subject line and sender. Processing mail this way however does not change its status -- it's still an "Unread" message, even if the user has read enough to decide to deal with the message later.

This becomes a problem when the user receives a large volume of e-mail. These "Unread" messages continue to distract, inflating the "Unread" message count and blending in with actual new messages to tax the reader's attention.

To improve the mobile e-mail experience, Pierce and others at IBM have been working on what they call the Mail Triage iPhone client, and a sidebar plug-in for Notes.

As described on IBM's Web site, the experimental iPhone e-mail client offers several new ways to categorize e-mail that are better suited to how people actually use mobile e-mail clients.

Instead of providing a set of folders, the Mail Triage iPhone client separates the user's e-mail into Untriaged and Triaged folders, with additional visual cues about the source, other recipients, and content of the message.

It also comes with set of tasks that let users specify whether a message is something that can be handled "Next," something that should be "Deferred" until later, or something that's a "Reference" not requiring immediate action.

It's interesting work. E-mail clients could do with some innovation.