There is a great blog post on Mashable that investigates how Zappos uses social media to build their brand at: http://mashable.com/2009/04/26/zappos/

Here's the post:

The New Social Engagement: A Visit to Zappos

This post is co-authored by Soren Gordhamer, author of Wisdom 2.0: Ancient Secrets for the Creative and Constantly Connected, and Paul Zelizer, author of Money Makeover 2.0: 5 Steps to Financial Well-being in Today’s Economy.

Krista Nieher covers Social Media at AdTech on the AdTech blog at http://www.adtechblog.com/blog/detail/the-next-frontier-apparently-its-s...

Here's the post:

The Next Frontier? Apparently it’s Social Media.
Posted by Krista Neher · Thursday April 23, 2009

Display based advertising is so web 1.0. What’s hot now is connecting with consumers beyond traditional display ads through social media according to the panel at The Next Frontier: Advertising in Applications session.

Moderator:
Mark Naples, Managing Partner WIT Strategy
Panelists:

Steve Hall reported on Pete Blackshaw's AdTech Keynote on the AdTech Blog at http://www.adtechblog.com/blog/detail/in-a-crappy-ad-economy-innovation-...

Here's the post:

In a Crappy Ad Economy, Innovation is Key
Posted by Steve Hall · Tuesday April 21, 2009

Long, long ago, way back in 2005, engagement was the cause du jour of mediaologists and media metricians.

Enthusiasm for the concept was so great that, for a brief period, agency and marketing personnel had "engagement" added to their titles: Chief Engagement Officer became the new meaning of "CEO."

By April 2006, the Advertising Research Foundation issued its official definition of engagement -- "Engagement is turning on a prospect to a brand idea enhanced by the surrounding context."