Sorry for the slow load & lack of narrative on the last one. The video can still be found here (but be patient with it.) Here’s a pictorial of what’s going on:
#1 – Go to www.seattleweekly.com
#2 – Click on Classifieds > Real Estate For Sale
#3 – It takes you to Trulia’s Seattle Weekly Partner Page http://seattleweekly.trulia.com/WA/Seattle
#4 – Using the user agent switcher for FF, change your user agent to Googlebot
#5 – Refresh the page. It now reloads as the page Trulia optimizes for (currently #3 for “Seattle Real Estate) www.trulia.com/WA/Seattle
What are the implications of this? Basically that Trulia isn’t playing it as clean as their PR guys would tell you. They’re intentionally screwing their partners (they’re doing this to Parade, as well) out of links back, and they’re picking up some nice one-way sitewides as a result. The results they’re getting probably aren’t worth the risk of a cloaked 301, but they’re sure doing it. Oh…they’re also doing a pretty stupid, easily detectable cloak.