InfoWorld has an odd article/"expose" that addresses a supposedly sneaky new way of making money in open source: selling subscriptions.
No matter what you call them, open source companies have been steadily integrating parts of the hated commercial software subscription model into their business. First it was support, and now it is software access.
Now, for anyone actually involved in open source, this will sound curious, since this is precisely how most open-source businesses have always made money. Witness Red Hat, for example. InfoWorld just described its model.
So, this "new" model isn't so new. It's also incorrect to suggest, as Savio Rodrigues of IBM has, that such models make open source proprietary in the traditional sense of the word. Proprietary software means that you can't look at or use software unless you get a license to that software. Last time I checked CentOS was shipping something that looks an awful lot like Red Hat Enterprise Linux, minus trademarks. Same with Oracle.
Every open-source company that I know can be forked. Ergo, it's open source.
Have MySQL and other open-source companies (Zimbra, SugarCRM, etc.) added proprietary software to their offerings? Absolutely. Is this a trend? Given that these companies have done it from the beginning (including MySQL, which everyone seems to forget or simply not know), I'm not sure if it's a new trend (like the InfoWorld article implies) or just a failure to kill off the old software trend of locking things up in order to make it convenient for the vendor to charge.
Indeed, I see the trend away from proprietary continuing, and accelerating. Look at what is happening with Yahoo!, Verizon, Cisco, Microsoft, etc. etc. etc. Opening up. Slowly, but surely.
Look at the rising numbers of open-source companies who give away most or all of their code as open source, including the companies listed above. It might warm the cockles of proprietary hearts to think their 20th-century business models will persist into the 21st Century, but the proof points the other way, though not to an obliteration of proprietary business models. We'll have those so long as Neanderthal software businesspeople persist in looking backward rather than forward...which will probably be forever.