Well, it's just about 3 1/2 days into my current experiment. So far, I've promoted 78 different items in the Etsy Promo forum. I'm not sure if there is any direct correlation, but out of those, 9 have sold since I promoted them. I'm truly happy for the sellers of these items...even if my promotional effort didn't contribute to the sale. Every day, I'll continue to promote my fellow Etsians, and I will be just as thrilled to see the "sold" sign appear on my favorites listings as I would to see my own items sell.
Here's hoping that the upcoming holiday shopping season is an overwhelming success to all who are actively trying to make their Etsy shop's a success.