that depends on your objective. what is that you are trying to achieve with video marketing. trying to get your own video across? or trying to drive traffic to your site? or just get backlinks? if done properly, video marketing can be verry effective and can drive decent amount of traffic to your site. but that depends on niche as well as not all niche will offer the same about of video site traffic
youtube submitted video may give a lot of traffic, because youtube is the trusted resource for google, so if you optimize the title and description correctly, your video will immediately have good rankings
video submission or video marketing is a big part of internet marketing strategy. I use traffic geyser in doing video submissions. You can use tubemogul as well.
Your Video brings you traffic only when you have good content in it presented in best way. Also it should be made popular too. So more or less you need to promote the videos in all the sites
I have gotten excellent traffic and even some sales from the videos we've done highlighting some various aspects of firearms we sell - that being said, i did spend some time putting these videos together and tried to create it to be as informative with a "cool factor" as possible! high quality video is a must - Vimeo is an excellent alternative to youtube, but I use both.
We get good traffic from both YouTube and Vimeo! Of course the HD is cleaner on Vimeo! See for yourself here... http://vimeo.com/jvfconsulting
It's a good technique to promote your site product or service. However, from my experience I find that it is more suitable for entertainment/celebrity related websites. For any other professional service or product, I think search engine traffic is more relevant.