It always takes time to promote a site, so I guess there might be some lag between you move into a server and get real traffic for your site.

Shared webhosting is not possible. You use too many resources.
Atleast a vps with a lot of traffic.

Guys we host plenty of youtube sites that work just fine on a shared host.

You have to realize that less than 1% or so are ever going to become popular, and if you do, then is the time to start shelling out the cash for a dedicated server. Don't waste your money if you don't need to.

If your site does become popular, then moving to a dedicated server is not a huge ordeal. Just ask your host to move you to a dedicated server.

My suggestion however is to move to a dedicated sooner than later. Anything using more than 5 gigs of space is a very good candidate to start considering a dedicated server because transfers of sites that large can be problematic when trying to migrate from a shared host to a dedicated box.

The sooner you can go dedicated, the better, but its hardly worth it to do it in the very beginning unless you are a skilled marketer and you know with 100% certainty your site will be a success.

I speak from experience that a shared box can be just fine and I cannot think of one youtube site that we have suspended due to it being a problem. You are not going to be instantly popular in a matter of minutes. It takes time and in that time you can work with your host to find an appropriate solution, which is probably a dedicated server...

if you want to have a good website, invest and get better gains is a VPS, So to sum him you have to prepare the VPS with players and codecs, and talking about seo will help you have your own IP and a server more stable

I think it is impossible to have video files on shared hosting as this will lead to server overload and as a result to account suspension.