Going by the front page article (-> http://www.renderosity.com/prime-time-begins-monday-july-18th-cms-15702) it would appear that it (-> http://www.renderosity.com/mod/bcs/index.php?ViewProduct=87657) doesn't officially launch until Monday.
I suspect that this means they won't update the site menus until then.

My guess would be the MP item slipped out a little early and was then removed/hidden, because it's not showing up in either "What's New" or on Store Staff's store page, but fortunately Google did index yesterday, so allowing me to know what you were talking about.