Even though it lists the Yamaha at the top, the article is being unfair to it. The Yamaha HAS front height channels. It is their own, proprietary version (which they call "Presence"), which they have been doing longer than Dolby and Audyssey. Basically, the chart has been done in a manner to exclude their front height, but includes everyone else's.
You can look on the back of the unit and see this when looking at the labeling for the speaker terminals.
It is also worth remembering that in ALL cases, these channels are artificially generated; there is no current format with discrete (or even encoded) front height channels. So there is NO reason to exclude Yamaha's version of this.