Holy moly Batman! Magnificent news. I bet if the movie does well, a new series won't be far behind. Fuji Terebi is desperate for hits nowadays, and there's no surer fire bet than Hero 2. If I'm not mistaken, no trendy dorama has ever broken Hero's 34% viewership rating, desho?
Edit: Ok, I just checked. The special scored a rating of 30%. This strongly indicates that the same huge crowd that tuned in for the original will be around for the sequel. In an age where Fuji should consider itself lucky when something breaks the 20% barrier, a Hero sequel and its almost guaranteed 30% audience share is a no-brainer.
I am almost certain now that a new season has already been cooked up, they just haven't gotten around to announcing it yet.