Yes, the IKEA Home Planner is available for Mac OS X, but it's pretty limited when it comes to supported versions of the OS X.
According to official website, you can install the application on MacOS X 10.6 Snow Leopard or higher (for Intel processors only), not compatible with Mac OS X 10.7 Lion. Since 10.6.8 is the latest one, you can run the application betwen 10.6 - 10.6.8.
To find additional information access the official website: http://www.ikea.com/ms/en_JP/rooms_ideas/splashplanners.html
