I agree that porting Theater View over won't be a simple task, with the lack of Direct3D.
However, MC can already use the Quicktime Engine for video playback on Windows, and the MacOS version of the Quicktime Engine is much more capable. It might not be as challenging as you suspect. Now, will we have as
nice of a solution as MadVR+LAV? Certainly not.
However, I don't think it'll be impossible if their architecture is really as flexible as they say. OSX has a lot built into their APIs.
One thing I thought I'd mention briefly... To replace Red October on MacOS.
Perian has long-been the go-to "codec pack" for Quicktime on OSX that allows the Quicktime engine to support XviD and MKVs and all of that good stuff. It works very well. Unfortunately, the Perian developers for their own reasons, have decided to move on to other projects. The last release of Perian is coming out soon, and then they are going to release the source on GitHub (or Google Code), and stop development.
I actually think this could be
even more of an opportunity for JRiver, if they choose to pounce on it. LOTS of Mac users (including the "internet famous" high profile ones) are going to be looking for something to continue on in Perian's name. Sure, there's VLC, but that isn't the same thing at all (and the OSX version of VLC, while improved from days of yore, is not the same as the Windows one, and is decidedly clunky on OSX).
All they'd have to do is take the Perian source, modify it to work with whatever video engine they develop for the Mac version of MC (and follow the license terms as they have with the other open source projects they've used), and we can have
Red Perian, the Mac OSX corollary to Red October. I'm sure, if they try, they could even make it much, much better. Especially with suggestions from wizards like you, Nev, and Madshi.
I do agree, and I think Jim made clear, that the project would not be a simple one. Their back-end is apparently ready to be ported, but it'll still take a substantial amount of work. I think that much is obvious.
However, I also think it could generate substantial rewards. Apple owns the high-end market for PCs and Laptops. Us old-school geeks might not like it, and I certainly don't like some of what they do myself, but the fact remains that if you limit it to PCs over $1k, they are crushing all the other manufacturers. These are GOOD customers. While their overall market share numbers remain relatively low, that's now primarily overseas markets (which are shifting, just look at China), and corporate PC sales. But, are those corporate PCs the "market" for MC? Plus, they're now sucking all of the profit out of the market at the low-end too with the iPad.
That's why Microsoft reacted.