It's quite impressive to watch Cassandra Clare maintain the tension and intrigue all the way into book 5. She does this swiftly, filling the gaps with Simon's woes of his estranged relationship to his mother, and Alec's unease with his boyfriend's immortality. Most importantly, the story didn't feel exaggerated in any way or prologued for the sake of word count.
Sadly, due to the unpopularity of the first film, the sequel has been postponed. Fans can at least rejoice that the books are now all in print and reread them at their own pleasure.