Many people will need a blood thinner in their lives. While the very term creates confusion, the blood is not really thinned, it is made less likely to clot. The previous "gold standard" was warfarin (Coumadin)--yes, it IS the same ingredient in what many of us know as rat poison, yet is carefully controlled in humans.
What this means is that if you take warfarin, you have to go to the lab frequently at the beginning and then less often in order to make sure you don't bleed excessively. All in all, blood thinning is a balance of thin enough to prevent abnormal clots--yet still able to stop bleeding from usual cuts and scrapes.
The latest "next thing" in blood thinners is found in a new family (class) of drugs known as factor 10 inhibitors. The first you should know about is Pradaxa (dabigatran) and a second (rivaroxsaban) received a lot of press at the recent American Heart Association meeting (see ROCKET AF), yet dabigatran is getting the nod from many experts in the anticoagulation field. The difference with these new medicines is that the "warfarin style" blood tests (protimes or INR) are simply not required.
The next few months will help sort out the research and reality, but I think dabigratran will take the early and sustained lead.