Hey, I think it will be great!
I go in the Xbox forums occasionally and they have a really good thing where you enter your gamer tag and that shows up with your gamerscore, your awards and a bunch of other stuff as well as your forum rank.
It's always nice to level up
Yes this would be great. It can easily be accomplished too with user rank titles and images. Since this is a nintendo forum you should come up with Nintendo-related tiles/rank images from various Nintendo franchises. I've seen this done in the past on other nintendo-based forums and it tends to work very well.
I think what he means is somewhere, it should be posted what people will achieve at certain post counts. Like
1-10: Yoshis Egg
11-50: Pokemon trainer
51-99: Young Lonk
100-?: Invisible mario
I'm not actually sure these are the post counts required, but they are the first few titles.
It should be kept in this topic though.