We would if we could, but as far as I know Facebook doesn't allow you to put a permanent banner anywhere on your pages. If you want to let people know when you fuel-up, you could take a look at the instructions here for using a Fuelly RSS feed to import fuel-ups to Facebook. I posted that last year, but the process should roughly be the same.
ok, I see. I'm not trying to be mean with this comment I'm genuinely curious—do you like apps that do that? I don't use Facebook that much, but when I do log in I find all of those I exercised today and I just planted a virtual garden updates annoying. I know people must like them, I'm just not sure I want to create one of those because I personally don't enjoy them. I'd rather see human-written messages from my friends than messages from the programs they use. The same is true at Twitter which I use way, way more. I usually unfollow anyone who has a bunch of automated updates.
I understand Facebook is hot and everyone is there, I'm just not sold on app integration.
Personally, I have almost no facebook friends who use fuelly or are interested in logging mileage. Those who are interested are already on fuelly, so I would not be interested in a facebook app. I'm also the kind of guy that hides basically every game or application from my news feed though.