Not much news that I have heard back from the HarperCollins movie rights department, at any rate, Mikey.
There was a flurry of interest when the first book, The Court of the Air, came out.
It was actually shortlisted as the only fantasy/SF novel to be presented to film producers at the Berlinale by the event organisers (it's the world's largest film festival).
Bad timing, though, as The Golden Compass had just tanked at the box office and all the film producers were running for the hills as far as fantasy flicks were concerned.
I'd remain hopeful, though. HarperCollins have a great track record of books-to-movies... aka The Lord of the Rings films, the upcoming Hobbit, the Time Traveller's Wife, the Narnia movies, etc etc.
Just give it time, is what I'd say.