Priceline has gotten so liberal in their quality ratings, especially in large cities, that if you really want a 4* hotel, then bid for a 4.5* in zones where 4.5* is offered. Other than that, all you can do is send your feedback to Priceline.
Editorial by Sheryl: It's such a shame that Priceline's Name Your Own Price product has been so compromised lately. What once was a complete shoe in as a great deal, is no longer there with ratings of some hotels. Don't screw your customers, Priceline. It will come back to bite you.