My gauge used to point right in the middle (no normal letters, I have the universal picture for temperature). I replaced my thermostat with a 195 degree stat 2 weeks ago when I flushed my coolant. Now the needle points below the halfway mark... it hangs around 35-40%... sometimes dipping even lower.
Yet, when I have my OBD-II scanner hooked up, monitoring realtime, the coolant temp averages 190 to 195 degrees. Go figure.
-RB