Development of Characters

I saw that a lot of people wrote about the storytelling style of Two Towers this week, and I was thinking about how the character development is unique in the book.  In the Fellowship of the Ring, it mostly focuses either on Frodo or on the Fellowship as a whole.  We do not see a whole lot of individual character development.  There is an awful lot that happens concerning the plot in Two Towers, and Tolkien somehow manages to also develop Aragorn, Merry, Pippin, Sam, Frodo, Gandalf, Legolas, Theoden, Gimli, Saruman, Eowyn, and even Gollum.  I think he does a masterful job of giving each character their own storyline that deepens their role in the overarching plot.  We see Pippin become braver and take initiative to take care of himself and Merry, Legolas and Gimli become good friends, Sam becomes stronger and wiser, Gandalf reveals more of his magic and strength, and so on.  However widespread the Fellowship is, Tolkien still manages to make each one feel real, unique, important, and developed.  He does a good job of weaving the tapestry of the story while not letting any of the characters become stagnant.