Sgt_Kickaxe - 8:16 pm on Oct 29, 2012 (gmt 0)
Embedding YouTube videos doesn't seem to affect my sites either way, Google seems to ignore them as far as ranking is concerned. That's my experience.
I've shared that experience, you are unlikely to see any direct rankings benefits from simply having the video although if your visitors actually watch them your site metrics might improve a little in terms of time on site. The effects really seem to have been zeroed out by Google.
Several years ago Google adjusted their algorithm to deal with a huge surge in the number of "video sites" that merely displayed videos from youtube and other big video sites. These types of sites worked for a while but haven't in some time, its possible that Google does check for ownership, only Google knows.