It was mentioned briefly on the theories page of "Lighthouse" that two of the names on the lighthouse wheel are darker than the others: JARRAh and SHEPHARD. I noticed this immediately when watching, as I'm sure many of you did. ("SHEPHARD" is so bold, it almost looks as if it was gone over more than once, although I don't see any extra "stray" lines.)
One theory was that it may have been intentional -- just so they'd stand out for us. I don't accept that idea - it was WAY too obvious. These two names in particular seem to be either written intentionally more darkly (by Jacob?), or possibly just much more recently.
Also, KWON and FORD are in all caps -- as opposed to the majority of the other names. I think it's clear that there were no fewer than two people who wrote names on the wheel. (Maybe the "keeper of the island" picks candidates and writes them as they go until the wheel is full. And then, who knows what? It starts all over again?)