The interview in MSXBox World contains mostly questions about the Xbox 360 version, but when asked "will there ever be a time when we can have Darth Vader and Yoda on the same console?" Sasaki gave a clear reply of "we don't have any plans for that." The interview is dated August 31st, 2008, but we are going to assume it is from July 31st.
This is contrary to earlier reports on the official Korean PlayStation site claiming Yoda will be available for download from the PSN. And videos like this certainly won't help douse those rumors.