Yeah, but how many people actually own a Tobii eye tracker? How many people have even heard of the Tobii eye tracker? To me, back when this patch got released, it seemed like a huge waste of development time. (Not to mention how it broke compatibility with a lot of mods that used custom versions of pre-Tobii scripts and/or modules.)
Occullus rift would have had a bigger audience I suppose, but still it's kinda cool.. who knows eyetracking might become standard in future computer monitors so might aswell get on the bandwagon.