For letter landing pages, which font and type size is best? What kind of testing have you guys seen in this area? Serif? Sans Serif?
Arial for fonts above 12, sometimes for 11. Verdana for fonts 11 and under.
On marketing items for OFIE’s, salesletters etc, we will use Arial but sometimes for a short large headlines and for a more elegant look we might use a Serif, something in the Times family, not bold and with some good line spacing. If the headline is long, we’ll stick with a Sans Serif.
These combinations have proven to be successful for us, but you should certainly test your own pages to see what resonates with your audience.