Louise over on the twilight lexicon forums posted this article. In a nutshell, it discusses the possibility of Taylor being re-cast and the other choices that may or may not be being considered.

I'm a gullible person, but I've been pretty realistic about the rumors lately. Brenda and Vanessa being considered for the role of Leah? I'm not putting much stock in that. However, this article seems to be pretty balanced. It's not making any radical claims, and it's leaving open every possibility. :) Hopefully it's a sign of things to come!