50 Exalted Reputations

Whoever posted that screenshot gets +1 internets.

People need to realize that this is a GOOD thing that they are updated the title. The title gets EASIER and EASIER to obtain as more reps are added to the game, it is only natural to make sure that the title stays as the epitome of Rep grinding!

This update ensures that random people don't get the achievement as the total amount of Reps increases over time. You should be thankful they are making it so this title and achievements STAYS hard and will ALWAYS require work.

It makes perfect sense.

From my count, 7 new reputations were added in Cataclysm. (At this time, I am assuming the guild reputation does not count as a faction). If you had exactly 40 exalted reputations at the end of WotLK, you will be able to hit 47 fairly comfortably simply by championing factions and wearing their tabards.

You will then need to scout around for 3 more reputations to grind up reputation with.

If you have not done so already, a reputation that is extremely easy to get is the Thorium Brotherhood. It used to be much more difficult, but has been nerfed to oblivion since Cata. Buy off about 20 lava cores or fiery cores from the AH, turn them in with Darkbargainer in BRD. It will be enough to get you from neutral to exalted. If you are human, or have extra reputation from guild perks, adjust accordingly. Get to him with a mole machine.

If for some reason you are not exalted with the cities, wear their tabard and go run stratholme. If you're lucky, you might even get a mount.