I suppose by "no one" you mean major news outlets. But the car blogs have no problem posting estimates based on what we say here.
Right, but the average person doesn't read car blogs and tends to discount what they say (even though they often have better facts than the major news outlets). People who are "into" cars have already made their minds up positively or negatively so it's not going to change. Also there is a difference between "We sold 1000 cars this year" and "In May 2012, 376 cars were sold".
Keep in mind that Automotive News is a trade magazine and not exactly widely read. I think you would have difficulty finding a copy at retail. So while the figures sometimes get picked up by the blogs and such, it's not like the general public can get a hold of them. For that matter I'm not sure the general public really cares.
To a car nerd like me, I'm all over that sales chart when it comes out every month! Always fascinating to see the trends and the new releases, how they are selling.