I booked my flight and hotel for GUADEC last night. And despite the talk about lodgings being hard to find, I was able to reserve a room at the first hotel I called.
If anyone is flying from the US and still hasn't bought their ticket yet, here is a suggestion: go directly to the Iberia website. I originally tried Orbitz, Travelocity, etc. and the flights were all significantly more expensive and much more circuitous. No thank you, I'd rather not fly Chicago to Detroit to Newark to Madrid.