I see a spike in traffic on Wednesdays, but thats probably because I have Wednesday off the real job and have time to put into new listings and promotion... Sales seem to pretty much reflect the amount of effort I'm putting into it from my end-- online attention spans are pretty short!-- Interestingly though I have noticed almost every sale I've made has been late at night after a higher traffic day-- maybe people have the day to think about it then its still on their mind at bedtime, or, maybe some insomniac shoppers out there lol