Did you use a video plugin to post the vids, or stick the code directly into a post?

If you directly added the code then http://eisabainyo.net/weblog/2006/05/26/find-and-replace-text-in-mysql/ is the way to do a "find and replace" in a database table.

Thank you EdB;

We had used both methods, SQL find & replace is ok. We will try to find a way for posts via plugin.

What you recommend for future use?

So for the stuff added via a plugin, all you have to do is edit the plugin. Find where it says dailymotion.com and replace it with the url that works for you. Oh and you might have to hit your "Tools -> misc" subtab and delete prerendered cache.

For the future, use what you like :) Directly adding the code is probably easier on your server (no rendering) but obviously harder when you want to make a change to everything. Using a plugin is kinda the opposite ;)