I'm a little confused about the use of web services with Flash. What type of data can Flash handle receiving? And does it matter what language the web service is written in (php, .NET, etc)?

Reading Adobe.com, it seems Flash can handle receiving just about anything back, even things like arrays. However, after attempting this and reading up on it elsewhere, it sounds like Flash cannot, in fact, handle receiving arrays or other complex serialized data. Can someone enlighten me as to the truth?