With IBMs launch earlier this month of Lotus Notes 8 and this week's unveiling of Lotus SameTime Version 8, industry analysts say we are beginning to see the evolution of the e-mail client from a communications tool into a coordination channel. And when that happens, IBM may be in the unprecedented position of getting a second chance at knocking off longtime market leader Microsoft Outlook.

[ See related review: Lotus takes unified aim at MS with Sametime 8 | Lotus Notes and Domino 8 show new life ]

Lotus Notes has seen 11 consecutive quarters of growth, with double digit growth in the past five quarters, according to Ed Brill, sales executive for Lotus Notes and Domino.

Kevin Kavanaugh, vice president for development for Notes and Domino, says that the latest numbers from IDC indicate Microsoft Outlook has a 50 percent market share while Lotus Notes has 40 percent.

Whatever the numbers, most industry analysts are now saying that with this version of Notes is finally on par and competitive with Outlook 2007.

By including Open Office, the ODF (Open Document Format) open source desktop productivity suite, IBM is giving companies an unexpected bonus.

"If I put Notes 8 on a desktop and want to include a spreadsheet in an e-mail, with Open Office I don't have to make sure all the receivers have Excel," says Karen Hobert, senior analyst at Burton Group.

But where will the arch e-mail rivals be in five years? A lot depends on how e-mail evolves, Hobert says.

In five years, we will still call it e-mail -- but only because it is hard to get people to change nomenclature, Hobert says. Nevertheless, business users will be working with e-mail in a very different way than they do today.

What users are witnessing is the morphing of e-mail from the primary communications tool on the desktop to the primary tool to coordinate communications from multiple sources such as RSS feeds, blogs, wikis, IMs, and voice. Instead of opening an attachment from a Word file, for example, today's e-mail clients simply use e-mail to communicate that a file is located somewhere. The e-mail tells the user where to find the file and provides a link to, say, Microsoft Sharepoint or Lotus ClickR.

"This promotes best practices, by putting content in a shared but secure repository and using e-mail just to communicate that it is there," Hobert says.

Web 2.0 e-mail client Zimbra now offers what it calls Zimlets, in essence mashups between the e-mail content and other enterprise information. If a user were to send an e-mail that included a Federal Express tracking number, the recipient could roll over the number and have the tracking information pop up in the e-mail rather than providing only a link to the FedEx site.

Hobert believes the real challenge for e-mail is not just to coordinate all of the many new forms of communications, but to figure out a process of notification so that users receiving information from one channel can be alerted in another.

"Web 2.0 is beginning to give us those kinds of services," says Hobert, pointing to technology that allows content to be found through tags or a user's Digg space.

The volume of messages will go down, says IBM's Kavanaugh. But in the new world of e-mails, they will trigger a workflow that may happen outside or from within the e-mail client.

Changed by the emergence of online collaborative tools, enterprise portals, social software, emerging enterprise 2.0 applications, and unified communications, we may still be calling it e-mail five years from now -- but we will be working with it in a far different way than we do at present.

E-mail will never go away, but it may get surrounded by so many other collaborative capabilities it will be unrecognizable from the e-mail clients we use today.