It's no secret that some of the guitars that shipped with Rock Band had some issues, mainly strum bar related. In a statement to Kotaku, they're owning up to the problems, and are dedicated to making things right.
As sometimes happens when new products first go into manufacturing, we discovered an imperfection with the strum bar in an early production run of guitars that were shipped at launch. We've since identified and fixed the issue in all subsequent production runs of the guitars. If users are experiencing a problem with their guitars or any of the Rock Band instruments, they can visit the customer support website ( http://support.ea.com/rockband) and we will send a replacement immediately. Harmonix is dedicated to creating 100% customer satisfaction and to the users who have encountered any hardware issues, we are sorry for the hassle.
While I applaud Harmonix for stepping up to admit fault like any good hardware manufacturer would (or should), there's nothing about this statement that should be surprising in how they're handling the issue. When you open the massive Rock Band retail package, one of the first things you'll see is a pink slip of paper that basically says, "If your crap is broken, go to http://support.ea.com/rockband for detailed warranty instructions."
So what are you waiting for? Don't procrastinate like I have been, using the Guitar Hero III wireless guitar and pretending like there is no problem.