So, since Wikimedia Foundation isn't interested in maintaining MediaWiki itself for third party users, how about we form a subsidiary company to handle commercial support, maintenance, install and hosting services? This could be a for-profit subsidiary, like Mozilla Foundation's Mozilla Corporation, if that makes sense.
I think there's demand for this, and it makes sense to do it under the Wikimedia umbrella.
Who's "we"? :) If you wait for the WMF board of trustees I doubt such a company will ever be formed. On the other hand, if a random guy, say Brion Vibber ;) (or some other MediaWiki devs), opened a company with whatever name and made an offer for this RfP, they could get this contract; and if things go well that company may develop in many ways, for instance becoming a partner organisation or even a Wikimedia thematical organisation named MediaWiki something. Just saying.
My impression from discussions I've had (and probably shaped by my own biases) is that there is more interest in another non-profit org to handle this.
In fact, the user group we're proposing this year is meant to demonstrate interest in MediaWiki from outside the Foundation. If the user group is viable, it will take over the release management.