Muglia made his comments during his speech at the Stanford Accel Symposium. Alfresco CTO John Newton posted some parts of Muglia's speech on Twitter. Muglia said that "at some point, almost all our product(s) will have open source in (them)." He went on to say that "if MySQL (or) Linux do a better job for you, of course you should use those products."
Various Microsoft products already contain open source code, such as MSN Messenger and Visual Studio, and the company also works closely with the Mono guys on improving Silverlight and .NET support on non-Microsoft platforms. A lot has changed since the days Microsoft would vigorously disparage anything related to open source.
Microsoft still has a long way to go, of course, and I hope that one day they will finally acknowledge open source in a more official way, and work with open source developers to improve their own products as well as open source products. A promise not to sue any open source project using vague patents would be a start. I mean, if the US patent office can't fix their own patent system, maybe companies ought to step up.
Then again, I also hope to see a live dodo bird one day, but that doesn't seem very likely either.