while most Smash Brothers related submissions are accepted, please remember a few key points:
1. "new challenger" pieces are BANNED. doesn't matter how much time you spent on it nor how pretty it is. they're not allowed as they're overdone and start fanboy arguments.
2. binder paper backgrounds are not allowed. please make the effort of taking those out before submitting it. blank white/black/etc. backgrounds are fine.
3. effort must be put into the piece. skill level doesn't matter so much as the work put into it. notebook scribbles stay in your gallery. if you want more people to see it, make a forum post and link it. only quality submissions are allowed.
if it's related to the Mario, LoZ, Metroid, StarFox, etc. series and not at all to the Smash Brothers series (i.e. Krystal, winged caps, Ridley, Gorons, etc) it is not allowed. as long as it contains a good amount of characters/items/moves... basically relevance to the Smash Brothers series, it's welcome.
if you're unsure, go ahead and post a question into the FAQ. i'll answer them and add the ones that come up a lot.
*note*
as for the screenshots currently in the club artwork, those are either submissions for the snapshot contest or my snapshots to promote the contest. more details can be seen in this entry: