OneTrueFan is a service to track web history, allowing web users to see what sites they spend the most time visiting. It also allows site operators to see their most active users, though only amongst those who have signed up for the service. You can read more about OnerueFan here.
Users accumulate points for a site by visiting, sharing links, and other activities. OneTrueFan rate limits point increases amongst players to one point every few seconds. I have no way to tell if this was intended to discourage gaming of the system, or is a coalescing mechanism for scalability which batches site hits every few seconds. Nonetheless for any site with a large collection of pages, at present it is relatively easy to take the OneTrueFan title.
Users who have installed the OTF browser extension see the web bar on every site they visit. Site owners can also install the web bar on their pages, making it visible to all visitors whether they use the browser extension or not. Hovering over the pictures in the web bar shows a list of recently shared links. My list of shared links is relatively tame. Its not difficult to imagine links to WoW Gold sales, or porn sites, or any of the other innumerable schemes which spam is used to peddle. The potential for mischief is there.
It is possible that OneTrueFan already has effective spam controls, focussed on the shared links rather than on obtaining the top spot in the fan list. I did not create a profile with spam links to check, nor do I intend to. In any case I expect they realize the importance of effective spam controls for a service which inserts content into other websites, and need to continue to focus on it.
Update: In the comments Eric Marcoullier (co-founder and co-CEO of OneTrueFan) described the current spam prevention tools in the service, and discussed some plans for the future.