Seperating beginners from the rest.

[Maneko]

If its invisible, then begginers wouldn't work harder to become Experts because they wouldn't even know about it.

If I was a begginer and I saw an exclusive forum, I would want to work harder and become a better spriter to be a part of that super-group.

I don't know. If I were a begginer spriter and I heard of an exclusive forum section for expert spriters, I would feel motivated to work harder so I could earn a place on it, actually. But again, people can react different so I understand your point.

Still, in my opinion, keeping the "expert" forum hidden would be the best way to prevent non-spriters from going and spamming it with their hollow comments and "wise" advice. I mean, if they are so "wise" as they claim to, then why they aren't making and posting awesome sprites of their own?

Regarding how to classify begginers, middle and expert spriters, you guys could ask the local experts to donate a few of their best sprites and use them to form a list of examples:
- In the bottom of the pile you could put generic bad sprites, aka recolors, minor edits, head/limb swaps, weapons and "powers" pasted on top a game sprite, etc.
- In the middle you could put advanced edits (you still can figure the original base) and things like that.
- On the top of the list you can put the best sprites made by the best guys you have around, aka greatly done scratch made sprites and unique material like that.

Whenever a newcomer appears, a quick check to that list of examples should be enough to make him understand to which category he belongs, and later he can use the same list to check his own progress to see if he is still at the same level or if he is ready to go up a level. That way you can save a lot of headaches and explanations, since these examples would also destroy any excuse or manipulation attempt on the spot. (I can't imagine a guy dumb enough as to compare his neon green Sonic recolor with let's say, one of these Custom Sonic sprites you have in the main page and pretend he's at the same level as these guys.)

I know that no matter what you do, people will still bitch, flame and try to manipulate for attention, but I suppose that this way, you will leave them with less room to do any of that.