Last week, I bought a digital audio player (MP3 player). I run around Town Lake here in Austin about once per week and like to listen to music while I run. I made sure I bought a digital audio player with USB 2.0 connectivity.
Do I really need USB 2.0? Actually, no. What I really want is to shorten the amount of time it takes for me to transfer files from my PC to the player.
Features are proxies for the things users really care about. Instead of dictating what features should be in your product, product managers should focus on what users really care about. However, they must also take into consideration that consumers use features to simplify their product comparisons and buying decisions.