Just found this out today. Some probably know this, but if not it is very useful. If your quicktime files are experiencing a gamma shift when played back in quicktime player after exporting from FCP, make sure that you have the Enable Final Cut Studio color Compatibility button checked. Not sure when this option was added but it was not check on my computer. Once checked your files should look more like what you were seeing in FCP and not as washed out.
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