Fairly average for the price.
Everyone raves about The Millennium but I've stayed a couple of times and didn't see anything special. The price in the summer is of course high, but I'd rather be downtown if I'm going to pay $200 a night. There isn't much in the way of restaurants and entertainment nearby. The rooms are nice but the view is best toward the lake if you can get one. Otherwise you'll just see parking lot. Breakfast in the restaurant is good but service is slow. Overall I'd say try the Marriott or the Sheraton downtown if you want a good luxury hotel in Anchorage.