The Liberal Democrats have come out with this not particularly funny video on Boris Johnson. It is a surprisingly amateurish job, especially when you compare it to many of the unofficial efforts of Boris Stoppers.
However, it does show that British political parties are finally waking up to what many outside of those parties have realised for some time, which is the huge potential of websites like Youtube. Unlike terrestrial television, there are no requirements for impartiality and the videos, if good enough, can reach an unlimited amount of people.
So if political parties really get to grips with this format, then they could be on to a winner. But in order to do so they will have to take the whole business a lot more seriously than the Lib Dems have with this.