To someone watching the instant messaging market over the past few years—not just the public networks, but the more security-conscious enterprise market—it might seem instant messaging is cooling off. Companies that focused, for instance, on security and compliance, have been absorbed by older and more established security vendors. The herd of companies that sold instant messaging servers has thinned, some of its members simply folding up, while others moved into other areas.

At the same time, when we look over traffic patterns for this site from the past year, it’s hard to miss the fact that a lot of our first-time visitors arrive looking for our list of instant messaging abbreviations, which suggests that—like a lot of things on the ‘net—IM has achieved a level of ubiquity and permanence, its user base growing as new settlers arrive on the digital frontier.

If there are fewer IM-specific security companies in 2008, it’s in large part because IM isn’t something an IT manager either permits without reservation or merely bans; but because it’s so crucial to a mobile and dispersed workforce that no security vendor can neglect some sort of IM security or compliance offering. One could also argue that enterprise IM received something of a benediction in September, when Cisco announced its intent to acquire Jabber, Inc..

Instant messaging has also become something of a backbone for other modes of communication. VoIP offerings like Skype, Gizmo5 and Google Talk draw users in with free or inexpensive voice chat, but find themselves compelled to include some sort of fallback text communications for those times when network latency, lag and jitter make a good voice call impossible. Conferencing solutions, like Yuuguu, which we covered in November, use IM buddy lists and IM networks as the starting point for much more complex group collaboration tools. Though Facebook relies on users posting updates on the walls of its walled garden, it also sees the value of the IM metaphor, as do Facebook developers who have tied IM networks to the service with applications.

Finally, though it was first conceived in early 2006 and spun off as a company in April, 2007, Twitter, Inc. enjoyed absolutely explosive growth in 2008. A November Bloomberg article cites Comscore, which claimed global visitors to Twitter’s site increased fivefold from September of 2007. As we wrote this note we noticed that the Consulate General of Israel will be holding a press conference via Twitter tomorrow morning.

In many ways, Twitter has proved a more able conduit for information services than traditional IM. We set out to write an article about IM-based RSS repeaters and information services in June of this year, only to find what we called “a sort of software fossil layer that Internet archaeologists working a century from now may well identify as ‘The Late IM Enthusiasm Age.’” A boom of such software in 2004 had largely disappeared by 2006. Twitter, on the other hand, continues to expand the number of news agencies, Web sites, political campaigns and others who gather followers happy to receive updates in 140 characters or less.

Twitter is not, strictly speaking, the instant messaging we started the decade with, but with its friends and followers lists and a proliferation of desktop applications (like the excellent Twitterific or the Emacs-based twittering-mode.el, it represents a harmonizing of SMS and IM that demonstrates a wide-spread craving for quick communications.

Which brings us to 2009. With an economy in recession and a certain grimness in the air, some might be tempted to argue that instant messaging is a frivolity people will set aside, either in the name of productivity or—in the case of enterprises spending not insubstantial sums securing and archiving it—costs. Our prediction? Another good year for our IM glossary.