I'll start by saying my answer is not necessarily advisable. However, depending on your situation it should work.
If the items that users are creating always have the same template you could try creating a custom item resolver that falls back to using the Master database.
- Allow Sitecore to attempt to resolve the item normally.
- When it fails, look in the Master database.
- If the item is in there, make sure it has the correct template
- Set the found item as the context item.
Using this method, you can publish the items from Master->Web s normal, but you don't have to wait until publishing is completed to see it.
Once again, this should solve the problem, but it's up to you to weigh the risks of serving up Master DB content.