No Duh!
"While these kinds of heads-up displays are popular in films and fiction (and dearly wanted by this hack), the poor sales of existing eye-level screens suggests a certain reluctance on the part of buyers."
The crap resolution on these early devices are severely limiting the kinds of apps that will truly revolutionize mobile interaction. Once we get 720p or higher, then a whole slew of possibilities opens up. Also, a solid, uncompressed, low-energy, short-range WirelessHD standard needs to emerge for this very purpose.