Pleased Customers

Pleased customer = best advertisment

This is as true today as when this gloriously awesome sign was originally printed.

No, wait - it's WAY MORE TRUE. 

[O.K. there are no gradations of true, there is just true and not true. I know.] 

Actually it probably wasn't true when this was written - simply due the the practical limits of spread of the endorsement.

Although, maybe it was true if this was written for a small town before broadcast media, where everyone in town equals less than Dunbar's 150, and you could tell everyone about your super-satisfied experience.

[Remember - satisfaction does NOT drive positive WOM.

Only deviation triggers expectancy violation, either positive or negative, so you need to deliver more than expected.

Only SUPERSATISFACTION creates advocacy and positive word of tweet.

Any significant dissatisfaction will create a strong desire send out angry tweets, or videos, or posts.

{UPDATE: looks like startup GRI.PE is looking to facilitate and capitalize on this}

This is because expectancy violation causes arousal, which triggers memory formation and a desire to act.

Lots of memorable advertising, such as things that are humor, or surprise, probably work in the same way.]

Then it became less [or, indeed, not] true, when things like television advertisements were probably the best advertisements, simply because the reach advantage the had over unassisted promotion from individual customers.

But now it is way more true [or just true] - since theoretically a pleased customer could tell loads of people, relatively easy, assuming they were into social sharing and had been for a while, and would be perceived as unbiased endorsement, so would probably be the best advertisement.

Although, it might not be considered an 'advertisement' as it hadn't been solicited by the client, if you asked the FCC.

Zuckerberg certainly thinks so:

"That's true for ads as well. An advertiser can produce the best creative ad in the world, but knowing your friends really love drinking Coke is the best endorsement for Coke you can possibly get."

I guess it depends on what you mean by "best" and "advertisement".

If an advertisement is best but no one sees it, does it make a sale/increase price elasticity of demand? 

Oh never mind.

Nice isn't it?