All of Riven's clarifications are correct and no I don't think the skybox should count towards the brush limit either.
Great demonstration there Nib

Although I cant say for certain, it's been a year since I've been in Hammer but you might be able to make #4 and #5 one brush? Can't remember.
"Muhnay" said:
Will Player Clip Brushes, and Hint Brushes also count against the 20 count?
I think if it has a usability/bug preventing purpose then no it should not count. If it has a gameplay/practical purpose then it counts. SO the hint brush does not count (but I don't see why you would need one), the clip brush may count depending on the use. If it's to prevent a player getting caught on geometry then it doesn't count, but if it's to create an invisible platform or to stop the player falling out of the level then it counts.
Finger said:
I might actually have time to do something like this. Sounds fun. What game - Halflife 2 Deathmatch?
I think it should be open to all Source/Goldsource/Unreal mods/games as long as you follow the rules.
Edit: On second thoughts, we want everyone to be able to play them so I'm thinking.. let's make it HL, HL2 or HL2DM singleplayer or multiplayer.
I'm going to add the competition rules to the original post along with
NEW competition rules in bold and pink.
Regarding Displacements
To clarify with displacements, this is up for agreement but I think each displacement surface should count as a brush. That is, if you create a displacement from 1 face of a brush, that is counted as 1 brush, if you create a displacement from 2 faces of a brush, that is counted as 2 brushes.
To clarify this point, in the first screenshot there is a floating rounded cube. That was created from 6 displacement maps so that counts as 6 brushes.
Regarding Brushes
I'm surprised some of you don't know what a brush is considering it's basic level terminology.
A brush is a shape e.g cube, composed of multiple faces (polygons) and made up of BSP geometry. In source/goldsource the limitations for a brush are they they have to be convex and each face must be flat when viewing the face front on.
To clarify that last point, if you create a brush cube, then open up the vertex manipulator tool and select any vertex and move it that will create an invalid brush because it will create a non flat face.
So basically a brush is NOT an entity, NOT a displacement and NOT a model. If that doesn't help you, brushes are the stuff you must enclose your level in to prevent leaks.
As Riven said, you can see a brush as a "tool" so don't think about how the engine cuts up faces further in game that is not of consideration in this competition.
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