Before, house tours were very popular, and they were usually held as events. Basically, this was entering someone else's house and touring it, and at the end you would give the owner feedback. This was usually done for room ratings, a popular feature that was removed a while back in 2009. House tours still happen, and can be found in the "Grand Opening" section of events.
Room Decorating Contests.
Before, on Yoville.com there would be a room decorating contest that would be held once per theme. The winners of the contest would be able to win the newest yocash home for free! Sadly, these contests started to become rare and the developers stopped having them completely. Also, from time to time there were one or two room decorating contests on the official Yoville Forums.
Decorating contests have returned to YoWorld and can be found on the YoWorld Forums.