Yow, have NONE of you taken a statistics class?
The best information I can find says that length is normally distributed with a mean length of 5.877 inches and a standard deviation of 0.825. 7 inches is 1.3612 standard deviations above the mean, and thus the model predicts that 91.34% of guys will have a penis less than 7 inches long.
In reality, when purposely not bringing up penis size with guys I'm interested in, I'd say about 40-50% of the guys I've gotten naked seem to have been as big as or bigger than me. The best explanation I can come up with for this is that if you found some way of measuring insecurity and plotted it against penis length, you'd probably find a moderate-to-strong negative correlation, especially among homos. Since insecurity is one of those things I find really tiresome really quickly, I'm probably indirectly selecting for guys with bigger dicks by selecting for guys who are less insecure.