I acknowledge and welcome the investment in a new mtb track and I understand the reasons for the choice of location. I even believe that a few people may start mountain biking for no other reason than what they see on the TV during the Olympics. I will welcome their conversion with open arms. But I've tried, I've really tried to summon enthusiasm ("excitement" is going too far). I have opened and read this thread several times and then closed it off as I had nothing positive to say. Will it really deliver "the biggest boost in publicity for our sport for years?" Am I "excited yet?" Reluctantly I confess to feeling neutral on both of those questions. "And will it actually be good for mountain biking?" More boring neutrality I'm sorry to say; the best I can say is that I don't believe it will do it any harm.
What the sport needs is for one of the TV stations to get behind it and showcase the sport from start to finish. Take a beginner through kit choice, bike fit, early learning steps, training courses, progression from blue trails and on to black and beyond, the differences between XC to AM and on to DH, more kit explanation (suspension set up for ex). One of the important factors to communicate is that mtb is for all ages and that you can start at any age. The TV program could be in documentary form, or maybe wrapped around characters in a "drama" series for example. But is either likely to happen? Not in a million years!
But maybe that's not such a bad thing! Do you really want hundred's of thousands of new riders clogging up the trails? Selfish I know, but I don't.