This is something Frederick Samuel asks here, having presented a viral spot for Ray Ban (which looks, if you ask me, like it has been well post-produced to achieve this effect…)

My reply in the comments was:

good viral means good content and that will continue to be king, nevermind if it is an ad or not. think about it: people don’t forward it, because it is an ad for xyz, quite often, they won’t even be able to tell you the name of the brand or product a few days later.
the challenge with viral is really, to produce good content. to have a remarkable story worth spreading. with an increasing number of viral spots, it will be more difficult to stand out of the clutter enough to be liked&spread. but that is a challenge that classical advertising had all along, so there really isn’t anything new, don’t you think?

What do you think?