I'm currently trying to figure out how many different variations of the transporter room we've seen in TOS:
Transporter Room # 1
appears to be the old one they used on the Pike Enterprise in "The Cage". Opposite to the door is a star chart with the picture of a galaxy (probably our milky way). It appears to be the same one as in "Where No Man Has Gone Before" (though no ladder steps between the door and the transport platform) which also has the star chart with the star clusters vis-a-vis the one with the galaxy.
Transporter Room # 2
appears to be the one from the first season which has the star chart with the star clusters. Most of the time there are two interceding white lines running across the picture (flat screen display that shows the current position of the Enterprise where the lines cross?). In "Dagger of the Mind" there's the engineering display behind the transporter console (upgrade or wall display that is usually covered?).
If I'm not mistaken there's a funny moment at the end of "Doomsday Machine" where Kirk beams finally back aboard the Enterprise and looks disorientated for a moment as he realizes they used transporter # 2 to bring him back ("From this one I need to turn right to the nearest turbolift...").
Transporter Room # 3
appears to be the one from "Tomorrow Is Yesterday" which has a food / landing party gear dispenser / elevator. In "This Side of Paradise" we see two different transporter rooms. The one where Kirk and Spock are fighting doesn't have the star chart, it's probably transporter # 3.
Transporter Room # 4
appears to be the one from Season Two on. It appears to be the one with the additional monitoring console behind the transporter console.
Is that a basic summary or am I missing additional variations (I do not consider different positioning of the transporter console as a variation as I noticed in one episode that it changes its position several times while remaining in what appears to be the same transporter room. Maybe the console has a rotating ability)?