Let's see, what is the equivalent of this postcard today? Perhaps someone sending, via cellphone, a picture of herself writing an e-mail message? I am fond of ads and images that show off the new technology of long ago, and I guess in 1907 telephones still had some cachet as status symbols, like the iPhone and iPad today.
Wonder about the artist signature, "M.M.A." (A quick Google search turned up Mixed Martial Arts! Not in this case.)
There's a whole lot more of vintage to see at Beth's site, The Best Hearts Are Crunchy.