Potential New Particle or Fifth Fundamental Force?

Fermilab scientists today announced an anomaly in their collision data at the Tevatron which could point to a previously unknown subatomic particle, or according to some a possible new extremely short distance fifth fundamental force. Either result, if verified would be one of the most important discoveries in Physics in recent decades.

See New York Times and the paper at http://arxiv.org/abs/1104.0699