Influx Insights led me to an interesting post from a marketer (Dan Germain) at the UK's Innocent Drinks, pondering what makes viral content "take off." He reveals an interesting story which dramatizes viral's new role in agency/client relationships (though I'm not sure that was his intention).
He got a visit from an agency wishing to work with his brand, the agency had prepared a spot that wasn't quite their cup of tea, the spurned agency then posted the spot on YouTube and as of Sunday at 3:03PM it had 4,480 views. Innocent Drinks also posted it on their blog, asked brand fans to comment, and got many pro and con posts about the spot.
A few interesting points in my mind. First, posting on the blog brand lovers frequent seems like a great way to test a creative idea. Cheap, low risk, and probably providing a pretty reliable read.