IDC reports that fears about email spam and the explosive growth of IM in business points toward a downturn in email.

No surprise. Just as 40% of business phone calls end in voicemail, the store-and-forward nature of email means that we expect lag times of 24 or 48 hours before response to an email request. This is just too slow to conduct real-time business.

IM is propelled on the real time fabric of presence. You can see that your contact is online and available prior to initiating a discussion -- and in the increasingly wired, 24x7 world, people are more open to answering a short question via text IM in the middle of a meeting, because they know it will meanone less email or vmail downstream.

Of course, we will have to expect spim (IM spam) to become more of an issue, as the public networks try to transition to a for-fee premium services model. AOL has announced that it will be streaming video into the AIM client, so we can expect to see Lexus ads or movie trailers popping up on our desktops soon.

We will have increasing degrees of presence and availability filtering for privacy, like those already offered by AIM, MSN, and Yahoo, but even more sophisticated. I might wish to be available to the world only a few hours a day, but generally available to a small circle of friends, and always available to my closest cohorts.

But IM is inherently a better medium for filtering. A spimmer would have to get into the network in the first place, which is difficult unless accomplished by piracy ( like Trillian has managed to do). Even so, many levels of controls are in the hand of the user to avoid contact with unsavory people or spimmers, up to and including turning off all contact with them.

When I discuss IM use with those who have not shifted over to using it, I am surprised by a common attitude: the desire not to be intruded upon. Personally, I would rather have someone IM me and 'interrupt me' rather than delay the interchange and discover later on that a meeting has been rescheduled or whatever.

Perhaps the mantra of IM use is 'the sooner the better,' and those that are holding off on IM adoption as the primary form of e-communication just don't buy in on that principle. But they should.