Firstly, due to legal reasons, you cannot host or link hacks on this page, and you cannot upload different versions of the client. This is concrete and will be followed at all times.
Now, onto the rules, which are grouped by type.
All mods are welcomed as long as the legal rule is followed. Mods can consist of game-altering mods, multiplayer servers or map campaigns.
There is a lot of issues with worlds. It is difficult to define "good", so I will have to go through worlds on an individual scale.
However, please, use common sense when uploading. If you have only a dirt house, a level seed or anything that can be made quickly, do not upload it. For your own sake at least.
Unfinished worlds will not be accepted. Partially completed worlds will be considered on the basis of quality.
Also, try to upload substantial content. A huge castle will be more likely to get community approval than a cottage house. However, the key word here is effort. If that cottage house is more the size of a small villa and made legally, you may just be able to add it.
What is illegally made maps? Well, they aren't really illegal, but it's when an inventory editor is used on the map. It usually does not go down as well, unless your construction is the size of a literal continent.
The more effort you put into it, the more sure you can be that it will be approved not only by myself, but by the Minecraft community as a whole.
Textures are allowed to be uploaded. Texture packs preferred to individual texture mods (EG, terrain.png), but individual textures modifying a lot will be accepted too.
Also, we are no longer accepting Painterly Pack texture packs for multiple reasons to do with credit-giving and spamminess.
External programs (such as Invedit, Skinedit, RedstoneSim etc.) are allowed, as long as they abide by the legal rule.
No images and videos of worlds are to be uploaded as downloads, and have been completely removed from the image/video galleries. However, if you wish to get your image/video uploaded in our galleries, contact Kizzycocoa, and I'll see if the community would approve it.
For any questions about content, or for comments on your work (so to know if the community would accept it), please contact Kizzycocoa, or comment on this news post.
Remember, the Community Group is open to all download submissions, provided they also do not break any legal rules.
Firstly, we do not ban negative comments. That would be idiotic, and will never happen. People have opinions, and we should accept that, even the bad ones.
However, we do want to stem the inflow of suggestions and questions from fans. Not that they're bad, but your suggestions will never be seen by notch here, and your questions will likely go unanswered. To post them is just posting filler that, in the end, will never even be acknowledged by anyone from mojang.
Now, this does not mean they cannot be answered. If you want to still ask, please, visit the Minecraft forums to suggest a feature or ask a question. But we can't have the comments clogged up by these, when they'll serve no purpose.
Now, you're probably asking, why? Why am I adding these rules? Well, there's a simple answer.
The people who visit here and watch want Minecraft content. Not fan content. Every time they see something fan-like that isn't good, they get annoyed. Some even leave this page. This can't keep going on, for both the community and uploader's sake.
Thank you for your time, and I hope we can look forward to a much better future for the ModDB page!