I think "new" is less than two years. That's my opinion.
I don't consider myself new to horses. I have about 14 years. Though, like Ian, I am always learning new things, that does not make me "new to horses" and thus I am a "guest" on this forum.
This forum is for people who are so new to horses that they have a ton of questions to ask, and might feel hesitant to ask them out on the open forum becuase they think their question will sound "stupid" or silly or they just don't want to show their ignorance.
Well, you have to learn somewhere, somehow. You aren't born knowing. Althoug, in reality, I doubt anyone onthe wide open forum would make fun of a new horseperson asking a question that sounds ridiculous to them, this forum is meant for newbies to join together in their newness and maybe even take pride in it, because it IS exciting, and it DOES take courage to get started, to ask question, to reveal your ignorance. It's also nice to share every tiny triumph that a new owner/rider experiences; things that longtime riders might not remember as the big deal that they are.