This is going to be 450 feet according to this article: http://www.bostonglobe.com/magazine...L6J/story.html?p1=Article_Related_Box_Article
The Globe is usually very bad at getting development details right... I always take their overviews with a grain of salt. This one is particularly BuzzFeedy.
dude, i actually believe it, it makes sense when you look at the renderings of each tower.