2011 $1.37/peak watt
2013 $0.65/PW (today)
But, ah, once in place, you are set for your lifetime (should be good for 20, if not 30 years, with limited degradation), whereas you can be sure that electricity from conventional power plants will only increase. Consider life cycle cost in your final analysis. While this photo is just one of my sunsets, no doubt solar PV is at sunrise.