Suppose you had a product you were promoting related to helping people get top Google rankings. You could then do a search as follows on Google:
site:youtube.com intitle:"top google" views 1000...5000
What this search will do is return videos with between 1,000 and 5,000 views on YouTube that are related to the term "top google". (Leave the commas out of your search term for the view counts).
I try to keep the view parameters within reason. If you choose a range of from 1 to 100,000 Google has to do a lot of work and use up resources to fetch your results. If you do this too many times and too fast you may get the Google "spambot" notice and you may have to fill out a Captcha form or you might possibly get blocked from doing more searches for a time--not long, usually no more than 30-60 minutes.
Any time you scrape Google data, especially using "intitle, inurl, or site" commands you run the risk of having Google think you're up to no good--and then you can get the warning notice--especially if you do many searches with these commands very fast.
If that should happen, try clearing cookies from your browser and often that will take care of the problem without the time wait.
Now, right below the Google search box, once your results are returned--click on the "show options" link. Then click on the link that says "Latest". This will rank the results by date with the most recent showing first.
The reason I rank them by date is because I want to find videos with lots of views in the past month or so. If you don't do this you may find videos with lots views a year or so ago, but there may not have been much recent activity.
Once I find a good video getting tons of recent views, I would then post a video response to the video and leech some traffic from the page. Your video response will show at the top of the comments section (above the text comments).
Since there are often very few, if any, video responses to even very popular videos--you can get your video listed and some of the visitors will click on your vid. Make sure to use a graphic or annotation in your video to give your URL to the viewers. And keep it short, only one or two minutes.
One final comment. Include valuable content in your response to your viewers. If your video is total crud and the only purpose is to drain off visitors from the original video, well--that's rude and in poor taste. Furthermore, the creator of the original video will likely delete your video reply. I would!
Hope that's useful --Mike