Cutting Edge: Ra-den

prior to the release of patch 5.4.

Assuming this isn't a typo or placeholder, this implies we'll be seeing a .4 patch for the first time since BC. What could Blizzard have in store? :)

Pandaria and the Alliance-Horde Conflict are two entirely seperate themes in the Mists of Pandaria expansion.

As of Patch 5.0, we began to see the Sha manifestations form across the lands of Pandaria, with the Sha of Fear in Terrace of Endless Springs being the main enemy of the patch.

Patch 5.1 introduced Landfall: a Horde-Alliance conflict resulting in a PVP Daily-Questing Hub in Krasarang Wilds, and more to the story of the conflict between the Horde and Alliance.

Patch 5.2 will introduce the Ancient Mogu Thunder King as a threat to the lands of Pandaria, along with small conflicts between the Horde and Alliance (the two new reputation factions speak for themselves here). So while each patch is focused mostly on a seperate theme, there is continuously a conflict occurring between Horde and Alliance members.

It is good to see that we're expecting more patches this expansion. I'm really enjoying the content so far and hope to see more unfold.

These "Cutting Edge" achievements are Blizzards solution to raiders feeling like their accomplishments were cheapened when a few patches later, players could go in and easily defeat bosses that once caused endless hours of frustration. The only solace raiders previously has was "Check my achievement date, I got that so far before everyone," while now these provide a small reward for those who managed to clear heroic end bosses when they were current.

So far we have three achievements:
Cutting Edge: Will of the Emperor
Cutting Edge: Grand Empress Shek'zeer
Cutting Edge: Sha of Fear

And it looks like Blizzard will continue this trend in 5.2 with this one as well as Cutting Edge: Lei Shen

In 5.2 Blizzard will also be releasing "Ahead of the Curve" achievements for those that managed to clear end bosses on normal when they were current content.
Ahead of the Curve: Will of the Emperor
Ahead of the Curve: Grand Empress Shek'zeer
Ahead of the Curve: Sha of Fear

And again, Blizzard will continue with these achievements in 5.2 with Ahead of the Curve: Lei Shen

These achievements will be phased out over time, becoming unattainable when the new raid tier is released. Meaning that after 5.2 is released these achievements (Normal or Heroic) for Will of the Emperor, Grand Empress Shek'Zeer, and Sha of Fear will no longer be attainable.

Note that the titles are not linked to these achievements so if you didn't manage to get Delver of the Vaults or The Fearless, you can go back and get them later!