Assessing the open-source scorecard is complicated. A complete "state of open source" would fill many pages. But here are a few things that have struck me over the past year or two.
Large swaths of open source have become mainstream--to the point of invisibility. Jay Lyman summed this up well in the context of the last LinuxWorld. We've also seen large vendors, such as Hewlett-Packard and IBM, generally de-emphasizing Linux and open source as businesses in their own right.
Just to be clear, invisible is absolutely not the same thing as irrelevant. However, some open-source fans who feel the need to ally themselves with a highly visible movement taking on "the enemy" find this shift troubling. (See, for example, "Mike's" comment to the aforementioned blog post.)
Pure-play open source as a standalone business has largely proven to be marginal. There are many successful companies that leverage open source in various ways. But it's the cross-selling of other things--systems, proprietary software, and services, in the case of system vendors, or advertising, in the case of Google--that brings in most of the revenue.
Basic pay-for-support models tend to have low conversion rates and haven't mostly been big moneymakers. (Essentially a form of "FREE 3," to use Chris Anderson's terminology.) I discussed this point earlier in "Does Open Source Have More Value Within a Larger Vendor?"
The Linux desktop remains a niche. There was a time when the desktop looked to be the next great frontier for Linux. That hasn't happened. Ironically, Apple Macs, which are arguably even less open than Windows PC, have been the big desktop winners over the past few years--not Linux.
The record for open source more broadly on the desktop is mixed. The Firefox Web browser has been the poster child for open-source client success. But other projects, such as OpenOffice.org, have been better at pressuring proprietary software vendors on various fronts (standards, pricing) than at emerging as big winners in their own right. And, today, the action has moved far more toward mobile clients (where Linux is starting to have some degree of uptake) and in software running "in the network" than in the traditional "fat desktop" client operating system.
Which brings us to the next point. There's a tension between cloud computing and open source. I cover that tension in much more detail in "The Cloud vs. Open Source" but essentially, most of the open-source licenses that were written to require that modifications and enhancements to open-source software be contributed back to the commons don't apply when software is distributed only in the form of network services, rather than directly in the form of the software bits themselves.
More broadly, as the Free Software Foundation's Richard Stallman has been lately complaining, the very idea of the cloud can be seen as conflicting with "Software Freedom" principles, to which open source was a means and not an end.
Yet for all those points that are either in the debit column or that some would place there, it's hard for me to see how open source could be considered as anything other than a great success. As a model for how software is developed and how people collaborate, open source has utterly transformed IT.
Even when open source hasn't displaced proprietary alternatives, it's helped make things like open beta testing and trial versions commonplace--ubiquitous, even. When was the last time you, as a consumer, bought a software program without giving it a spin first? For me, it's been a long time. Yet buy-before-try used to be the norm.
That open source has fully inserted itself into the mainstream as a result strikes me as a feature, not a bug.