@B_Cogs Not happening for 5.4.- Greg Street (@Ghostcrawler) August 2, 2013
Note how he doesn't say "not this expansion", rather just confirms that, as many expected given their total absence from the PTR, the epic gems are not coming right now. Is this a good thing or a bad thing? It will certainly ensure that the value of the blue-quality gems stays high, for now at least.
But could this be another indication that there is a patch 5.5 coming? Epic gems would certainly be one way to push players into additional content without devaluing the Siege of Orgrimmar final raid content, and many are growing concerned that, with the next expansion likely to be announced at Blizzcon in November with a beta to come shortly thereafter, we could be besieging Orgrimmar for a long old time.