I play a lot of Play-by-Email, and have played quite a bit of Play-by-Post. One of the advantages of the medium is the ability to divorce the player from the character, since you aren't looking at them while you're playing, but instead focused on the prose. To make it even more immersive (and to keep an idea of the public facing stats) we use custom made banners in our posts. This idea was born from playing a lot of Amber in PbEMs- one of the ideas in Amber are Trumps- cards that depict people that can be used to contact them, and for travel. We always made Trumps to depict the characters, and that evolved into the banners. I find that it adds an element to the game- a couple of examples are below.
That is strange. They're showing up for me... but looking at it from my Pluspora account, I see what you mean. My other images in my other posts on snap.as are showing up fine. I don't know the difference in these.