Priceline for one, but also so many various booking sites, have changed the process of getting the best deals in Europe. Once upon a time, like when Arthur Frommer was writing his Europe on $5/day books, chain hotels were much more expensive than locally-owned pensiones, but that's definitely not always the case now. If I can get a good chain hotel in a good area for cheaper than a ramshackle place with poor plumbing, I'm going to go for the chain hotel! Almost always I've felt I've gotten better deals than suggested in Rick Steves' books, although I'm sure they're a reasonable place to start if you don't want to research extensively.