According to a brief article posted on DMNews today , Alec Casey, Exec Mktg Dir at Sports Illustrated says emailed renewal efforts have had low response rates, but they definitely boost response rates for direct mailed renewal notices that follow them if you can get the timing right.
I don't know how SI gets its email addresses, or if they contact those addresses in any way during the year until renewal time, and both these factors could hugely affect response rates. (Handwritten email addresses have a high likelihood of being data entered incorrectly compared to postal addresses, and emails go "bad" at a rate of up to 30-40% per year as people switch email boxes, these days often to avoid spam.)
