If youtube adds really irritates you and you are searching for a solution then here is one.
For firefox users, you can install Tubestop. TubeStop is Mozilla Firefox extension that easily blocks You Tube pop-up ads for the Mozilla Firefox browser. You can get it here, Tubestop(click to download). Another solution is to download easylist which is illustrated Here.
For Google Chrome user, solution is Youtube options.This extension gives you far more options to customize your video watching. It also does a fair (if not absolute) job of blocking many inline video ads. You can get it here Youtube options.