OpenEXR

Prologue
Richard Stallman makes a distinction between "free software" and "open source" that I don't really understand.
Act I
By and large I'm a proponent of open source and we release movie elements (like sound effects and digital models) into open source under a variety of Creative Commons licenses.
Act II
We do use a number of proprietary standards. One standard for delivering a motion picture is a 1920x1080 progressive scan image in a Quicktime format with ProRes422 compression. We use this format and compression in our shop a lot. Quicktime and ProRes422 are both owned by Apple. They make a reader for a PC but there's no way I know of for a PC to encode a ProRes422 with a Quicktime wrapper.
Why is this important? Because almost any lab we deliver a drive to can handle a quicktime movie encoded as ProRes422. It's a perfectly reasonable output codec. "Broadcast quality" -- whatever that means. And making the deliverable format a Quicktime movie means you can imbed a whole bunch of different audio tracks (stereo english, stereo M&E, 5.1 English, 5.1 M&E, stereo commentary...)
Every lab has Final Cut Pro 7 and can read these formats just fine.
Act III
So Apple is doing away with FCP 7 and gone right to FCP 10. Obviously a lot of houses are going over to other kinds of editing systems which aren't as favorable to ProRes422 as we've been up until now. What if your go to a lab and they're all like "We just have FCP X and a couple Digi-Beta decks. Oh, but we have an Avid and a Premiere system we do our serious work on, but those are both PC's."
Oof. Aaf. I don't know. Now this is getting harder. When Apple's FCP was the obvious go-to professional program, the codec that worked so well with it was perfectly fine to deliver in.

Tom Rowen, Joe Chapman, and Juanita Arias in Android Insurrection. Rebecca Kush calls this picture "Lord of the Quarry Dance".

So what do we do now? Will we be delivering picture as OpenEXR? Politically that's very appealing. And obviously if ILM is using it, there's some serious industry level backing for it.
Act IV
Are we going to abandon proprietary Quicktime format for OpenEXR image sequences? For many uses image sequences are pretty awesome. Not for everything though. Sometimes a Quicktime or an .avi is just nice, right? It's not a directory filled with a bunch of individual image files.
Act V
So I'm just wondering what we're going to end up with. Will Apple relinquish the high end of video delivery to Avids and Premiere systems? Will they work with OpenEXR? Blender does. AfterEffects sorta does.
Final Cut Pro certainly doesn't. It likes Quicktime movies* and really prefers one of a handful of codecs (including ProRes422). Premiere, on the other hand, will import image sequences directly but unfortunately does not support OpenEXR as far as I can tell.
Postscript
Yeah, I got no idea. We'll use FCP7 for the remainder of the year and probably through 2012. And we'll deliver in ProRes422. Other than that? I got no idea.

*It is possible, and not too big a pain the the butt, to import still image sequences inside Quicktime wrappers.