In Junior Fiction: Siobhan Dowd's The London Eye Mystery (website here). The author was born in 1960 to Irish parents, but died in August 2007, just as her career as a children's author was taking off.
In Senior Fiction: Catherine O'Flynn's What Was Lost is described in another post today. Another debut novel is Julia Kelly's With my Lazy Eye from Lilliput Press, described by OC Sophie Grenham as 'heart-warming' : she recently interviewed the author in the Independent here.
Also, there's Denis Johnson's huge new novel Tree of Smoke, reviewed here by Jim Lewis in the New York Times as 'a tremendous book, a strange entertainment, very long but very fast, a great whirly ride that starts out sad and gets sadder and sadder, loops unpredictably out and around, and then lurches down so suddenly at the very end that it will make your stomach flop.'