Europe in summer and Hawaii anytime are the toughest award seats to get. I have been to Hawaii three times on awards, booking 5,5, and 4 seats each time. My secret - book 330 days out.

In fact, you are better off booking the award flights first, then the award hotel stays. For example, on my last trip August 2005, I was able to get flights on UA using US miles to Lihue, and back from Kona. Once I had the flights I knew to book the Marriott Lihue first, followed by the Marriott Waikoloa. If I had booked the hotels first, I would have been screwed as there were no award seats to KOA but a lot coming back.