A full year ahead of schedule IBM has brought Lotus Notes to the Linux desktop. A Linux client for Notes wasn't expected until the arrival of "Hannover", the next major release of the Notes platform, in 2007. But Big Blue had a surprise up its sleeve, and this month it announced the availability of a Linux version of the current Notes 7 client.

Still, even a year early, what took IBM so long? According to company spokespeople, some 5000 IBM employees have been using Notes on Linux as part of the IBM's internal beta test program. And it's no secret that IBM is planning a steady transition to the free OS for many of its corporate workstations.

IBM ported Notes to Linux by using the open source Eclipse framework -- which IBM created -- to build the client GUI. Underneath the Eclipse widgets, however, there's a lot more going on. Notes is much maligned as an e-mail client, and its market share is declining versus more traditional messaging systems, such as Microsoft Exchange. But Notes, when combined with the Domino server upon which it relies, is about a lot more than e-mail. It's a full-featured platform for building complex, database-driven collaborative apps. Notes makes it easy for mid-size businesses, in particular, to build custom back-office applications on a tight budget.

The Linux client for Notes isn't a freebie, nor is it open source. But that's OK. Nowhere in the Linux playbook does it say that commercial applications shouldn't play nice with open source.

Just being able to run Notes on Linux at all is a coup, as it gives Notes-centric workgroups hope for an alternative to the Microsoft licensing structure for the first time. Tellingly, the Notes client licenCes are fully transferable; if you're running Notes on Windows today, you can re-install Linux on the same machine tomorrow and continue using the Linux version of Notes without paying any extra fees.

Of course, IBM won't tell you that it wants to encourage its customers to switch from Windows to Linux. Rather, let's just say that IBM doesn't think it's a bad idea.

So, dare I say it? Do I utter those five fateful words? "The year of desktop Linux" has been declared so prematurely, so often, that it's become something of an industry in-joke. But one thing I can guarantee you: This year, Microsoft won't be laughing. Not even a chuckle.