I recently read a somewhat contradictory article published on a popular website that surmised that there were no longer interesting cars in Japanese time attack, and how there has been a split in interest as nobody wants to build record setting cars any longer.  The article goes on by saying that while there are still plenty of mid-50 second cars at Tsukuba (ahem, breaking records), this lack of general interest in being the fastest is allowing companies to take advantage of a new market that caters to the hobbyist.  Of course this is an opinionated perception, albeit factually incorrect, and naturally everyone is entitled to their opinion, but it takes just a few minutes to see the holes in this side of the argument.