Searched, couldn't find anything, so did it myself: a listing of all gem changes for Cataclysm.

Gone through all the epic gems on wowhead and cata.wowhead to search for differecenes. As with all repetive tasks, there may be stuptid mistakes and/or plain oversights. If you find one, let me know, and I'll update it.


Spreadsheet on Google Docs

No idea. I just waded through all epic gems that are level 80 on WoWHead and compared using their item ID.

Though taking a quick glance, there seems to be no Mastery gem listed at all at cata.wowhead.com.


// Edit
Scrap that, something went wrong with my settings, checking now.

Fractured Alicite seems to be the first gem with Mastery rating on it. Not sure if its "Item Level 81" also refers to that it cannot be learned before level 81.

Wowhead is listing some of the early green quality gem cuts as 425 skill, so in theory you should be able to learn them prior to Lv80. But being that they require gems that are from Cata content, I'm inclined to say that they won't be trainable until 4.0.3 (Cata launch).

That is the most likely scenario, Cata stuff isn't supposed to get in yet. However, we can all remember the lockboxes etc. in 3.0.1 that contained Wrath stuff. Who knows, maybe Titanium veins can drop a few gems? But even in such a case people will need to learn the actual cuts.