As someone who lives in Texas, this film has more then a little interest to me. I, too, thought it was a dead project, until there was a big article about it in one of the local papers. And the article was all favorable. Thus, this is my take on the subject.
John Sayles' script is still being used as the basis of the film. It was just worked on, which is not unknown for most Hollywood screenplays.
One of the reasons Ron Howard walked, was he wanted to do a R-rated version of the film. R as in R for violence. And at the cost that it would cost to do it, the producers wanted at most a PG-13 version of the film. PG-13 as in violence.
We know that Ron Howard can do big epics. Look at his "Apollo 13," but the director of "The Rookie" may not be such a bad choice. Look at this portrayal of west Texas in that film. He knows his Texas and his Texans, because that part of the film was dead on accurate.
The only cast change I am aware of, is that Russell Crowe will not play Colonel William Travis, but, that change may be due more to a prior film commitment, then the fact that Ron Howard will not direct.
The filming supposedly commences in March in Dripping Springs, Texas, where a fairly accurate set of the original Alamo has supposedly been recreated.
It is also suppose to be the most accurate portrayal yet of what happened at The Alamo. That I will believe, when I see it. As you can't get two Texans to agree on anything that happened at the Alamo. As Uncleromulus has pointed out, I am especially interested in seeing how they handle the claim that Davy Crockett was killed after he surrendered and after the battle was over.
Enjoy the film. I am sure I will.