It is in unsifted and wont get to the newness sifted page until it gets 10 votes. http://videosift.com/unsifted

Promoted videos don't stay up for very long - unless they also get votes.

How long a video stays promoted is determined by how many other videos it is or isn't sharing the promote space with. The length of time it's promoted has nothing to do with it getting votes. Personally ive never seen a promoted video be up for only an hour. Id say the range depending on number of videos currently promoted is between two and three and a half hours(best guess)

But if we are only talking about a video being on the front page. That has lots of pieces that go into determining where it goes on the front page and how long it stays there.