It's not every day that the entire technical press goes bonkers over news in the open source world, but that's what happened last week, when Sun announced that it was buying MySQL. Doubtless, the pleasant roundness of the sum involved - $1 billion – helped, as did the fact that most of that was cash. But leaving aside the sense of satisfaction that events in the free software world should be suddenly thrust centre-stage, Sun's move does raise a larger question about the fate of all open source start-ups.

Ever since Red Hat bought Jboss for $420 million in April 2006, MySQL was clearly the leader of the rest of the business open source pack. It is used by many high-profile sites – including Google – as well as the vast majority of the main Web 2.0 startups to do the backend heavy lifting. It might not be in the Oracle class, but as Christensen's Innovator's Dilemma teaches us, relentless technological progress tends to mean that the underpowered underdog eventually becomes good enough for the vast majority of users, while the overpowered top dog – Oracle in this case – finds itself innovating for the sake of innovating, and adding ever-more features that nobody uses. This makes MySQL the GNU/Linux of the database world.

Most people – myself included – assumed that MySQL was heading towards a hugely-successful IPO, not least because this is what MySQL's CEO Marten Mickos, always led us to believe:

GM: Investors obviously expect something back at some point, so are you looking to get bought or to do an IPO?
MM: We're aiming for an IPO. We're actually aiming for an independent existence and to do that you need to do an IPO, but the IPO is not the aim, the IPO is just a step. People ask, “What is your exit plan?”, and we say that we're not going to exit.

The fact that he decided to take the money from Sun probably has much to do with the dark clouds gathering over the world's economies, and the resultant dampener they are likely to put on the stock markets and public offerings.

Never mind that Sun has been increasingly active in the open source world, with its donations of code in the form of OpenOffice.org, OpenSolaris and Java; never mind that in some sense Sun's origins go back to the roots of free software: the fact remains that probably the most important of the rising business stars has been swallowed up. The question is: are we seeing the beginning of the end for all the open source startups?

This possibility needs to be faced, because in the wake of Sun's high-profile acquisition of MySQL, other big software companies are going to be looking at similar moves so as not to be left behind in the open source game. MySQL's price tag was pretty serious money, but some of the other open source startups could probably be picked up for much less – to the extent that they would represent small change for the big old dinosaurs, especially the ones with more cash than ideas. A few of the names that I'd certainly be considering include Alfresco (enterprise content management), SugarCRM (customer relationship management), Hyperic (systems management) and Jaspersoft (business intelligence), but that's just the start: there are dozens of acquisition candidates out there.

In the event of some or even all of these outfits being gobbled up by companies with Sun-like ambitions, the code would of course still be freely available, since most of the top open source startups use the GNU GPL, sometimes with a commercial licence alongside. But the nature of the business open source world would be changed dramatically: no longer would it be made up of plucky startups, but of corporate divisions, which are inevitably more staid.

What the open source community needs to consider is whether such a change would be a problem for the larger ecosystem? Would it result in the corporatisation of open source, and the loss of the vitality that has propelled it to its surprisingly powerful position in just a few years? Would it lead to debilitating forks, as disgruntled coders stormed off to set up their own new projects, and maybe even new companies? Or would it, on the contrary, actually help the open source world expand even faster, by bringing additional resources to bear (Sun's main justification for acquiring MySQL)?

If the money offered is truly generous – as is entirely possible – why should the fledgling open source stars turn it down? The VCs who back them certainly won't want to, and maybe the employees of the company wouldn't either. So does the free software community have any right to warn against such a move just because it might damage that community? More to the point, if there is a view that such a transformation would be bad, is there anything that can be done in practical terms to avoid it? For example, should an effort be made to unite many of the leading open source outfits into one company to gain some critical mass otherwise lacking?

I certainly don't have any answers to these questions, but I do believe that people need to start thinking about them seriously. I fear we don't have much time before the knock-on effects of Sun's move begin to make themselves felt: Nokia's announcement that it hopes to acquire Trolltech, although not directly related, is nonetheless part of the same broader trend. And once a domino-like ripple of acquisitions starts to pass through the open source world, it will probably be too late to do much about it anyway.

Glyn Moody writes about open source at opendotdotdot.