I was already exalted with Cenarion Circle at the time I did this, but apparently it will push you to exalted with them too, so make that Brood of Nozdormu and Cenarion Circle exalted in 15 minutes!
Bosses in Temple of AQ 40 are currently assumed to be glitched, giving thousands of rep per kill, but doing the whole instance may take a bit and may not get you all the way to exalted. But, if you kill the first boss and move down to the bug trio, this is where you can take extreme advantage of this.
You kill Princess Yauj of the Bug Trio, she gives 550 rep x 5, so 2750 with guild perk. Then, once she is dead, you run out of the room, the trio resets, kill her as many times as you want for the same rep gain.
So,
1. Get to bug trio.
2. Kill Princess Yauj.
3. Run out of the room so they reset and respawn.
4. Rinse and Repeat.