I don't know, it depends on your perception of "casual style". For some it may sound like designers who are less innovative and daring with their collections, who just stick to the more "safe" stuff. if you're just looking for that kind of "casual" stuff, that looks about more or less the same as the range of clothes Topshop or H&M stock, at selling at ridiculously high prices, I recommend you look into Stella McCartney, although I must mention Burberry Prorsum FW 05 which deserves a mention as it updated English countryside chic/ the laid back look wonderfully well. I think the key with being fashionably forward yet casual at the same time is to tone down some of the designer looks with high street finds,
like you might pair this season's pencil skirt or puffball skirt with just a simple turtleneck jumper, a pair of tights and some flats, instead of going the whole nine yards with a victorian ruffle shirt, weight high belt and heels, which is the look most designers have opted for. Sorry hope that made sense, it surely sounded so much more coherent in my head
Anyway I'm not an inner-fashion-circle-r, so anyone else feel free to contribute