One key question is "what will cause interest rates to rise?"

If it is voluntary that will not be a bad thing. It will likely cause a relative contraction in the economy, but it has to happen some time. Real interest rates cannot stay negative  as they are currently permanently.

If it is forced by the markets (think Greece) that is not a good thing. In fact that is a really, really bad thing. Congress and the president need to get their fiscal house in order before that happens or the feces hits the fan.

John