A decent article today (Spanish) in El País discussing the current situation of the plans for bilinguilism in the Spanish state school system. The most immediate problems if of course the lack of teachers with a high enough level of English which means that if you are training to be a teacher and have a good level of English you may be in luck and be able to jump the queue for a position. The other positive aspect, long term, is that it is a long term project. Creating a bilingual stream is not something that can be done over night regardless of what politicians promise.
All in all a well-balanced article summarising the situation: http://tinyurl.com/7e8ooat