Research Director Chad White, from American email marketing agency Smith-Harmon has just published a short report, Retail Email Year-End Trends for 2008 (free PDF for download) based on their experience in 2008.
Amusingly, this report “destroys the myth” of the best days to send emails. The most popular days for sending promotional email are actually Monday & Tuesday (39%), followed by Thursday (37%) and Friday (36%). So, what is THE best day to send promotional email 
It is even more interesting to learn what were the top 20 retail email days of 2008. In the first spot is what they called ‘Cyber Monday’, in this case December 1st, with 70% of the retailers sending email on this day. Not surprising for the USA, 19 of the 20 positions are held by promotional email for Christmas or Thanksgiving promotions.
The resolution to take for 2009: have you made your calendar, organized all the important events of the year and noted the periods when you should be planning your campaigns? There is quite a nice calendar example in the report.
Very interesting report. Thanks for sharing it with us. Interesting to see where you fall in the spectrum. I always had my best sales on Saturday’s bucking the industry trend. But my demographic at the time was 60+ and I think the whole work week / weekend thing has less of an impact on those in the retirement zone. (Yup the older folks do indeed sign up for an like to buy from email.)