If you start using Final Cut Studio or Pro/Express with a Mac, forget about interoperability with the PC world. There is not a single intermediate format that works out of the box between Apple’s video software products and the PC products. Apple has not made the effort to support some common intermediate .avi formats.
I put an ad on a filmmaking forum to help indie filmmakers with color grading, and we haven’t found a single lossless codec that can be read on the PC right off the bat (and that includes the PC version of Quicktime which can’t read the Apple Intermediate Codec while the Mac version can). Even the .mov uncompressed version someone sent me didn’t work (seems that the format has somewhat changed in the latest version of FCP).
There are few ways to do it: you either export in DVCProHD on the Mac and then you buy the Raylight decoder/encoder for $200 on Windows, or you buy Cineform on both platforms that costs much more than that (my personal preference would be Cineform if cost was not an issue). Another trick is to load the lossless video on the Mac version of After Effects and export again from there, but that costs another $1600 and it takes lots of time.
This would be a great opportunity for Lagarith to step in and port the codec as a Quicktime component for the Mac and part of ffmpeg on Linux. This way, the open source Lagarith codec would be truly useful and help in an area that right now is simply a no-no area. Heck, the guy who maintains that could even charge some money for it. That’s how big the need is right now.