1. A method comprising: measuring a state of a wireless channel on which information is received; using the measured state to select from a codebook a plurality of N codewords which optimize a predefined measure, wherein N is an integer greater than one; reporting a first codeword of the N codewords which best optimizes the predefined measure; and reporting a second codeword of the N codewords that next-best optimizes the predefined measure after the first codeword, wherein a best interpolation between the first codeword and the second codeword represents a better optimization of the predefined measure than both the first codeword and the second codeword.