With iTunes 6.0.2, you can now share your iTunes videos with others. However, the only videos that appear are ones that have been added after the update to 6.0.2.
To allow all your videos to be shared, move them from the iTunes folder to another location, delete them in the iTunes application, and then drag-and-drop them back into iTunes. This works for all video types that iTunes supports.
Mac OS X Hints
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