Up until the XBiz show where the FBI agent who supervises 2257 inspections spoke to the industry, I strictly interpreted the law to require a 2257 notice at either the beginning or end of every video.

Agent Joyner said that they were looking for a 2257 link on the page with the video or on the video itself. He stated that if there was a link at the bottom of the page, he considered that compliant.

What Chip says is very relevant--if your clip is used somewhere other than that page having the notice at the beginning or end of each clip keeps the video compliant. If you have absolute control over your vids, having a notice on the page will keep you compliant according to the FBI agent that is supervising the inspections. To be completely safe, put a notice at the beginning OR end of the video will keep that video compliant.