That is a great concept and if it wasn't an online site, but rather a stand alone application I might consider it. I myself don't really want people tracking my hunting spots and activity that closely. I definetely don't want my wife to know how many hours I spend in the field.
Let us know if you register and how you like it. I set up a hunting/fishing blog a few years ago to journal my activities. Now that I have found Huntingnet I pretty much post all of my activities here.