With the new DLC/Update leaked and it appearing to take place on Europa (a moon of Jupiter), and with the name "Rise of Iron", it clearly involves the Iron Lords. Combine this with the fact no one knows what happened or where they went after Six Fronts. When you start adding in the fact the Nine are commonly associated with the Jovian Colonies... Jovian being Jupiter... it isn't hard to believe. Especially when one factors in that there are NINE Iron Lords, each having a weapon that carries their name.
Efrideet - Efrideet's Spear
Gheleon - Gheleon's Demise
Perun - Perun's Fire
Jolder - Jolder's Hammer
Radegast - Radegast's Fury
Silimar - Silimar's Wrath
Felwinter - Felwinter's Lie
Skorri - Skorri's Revenge
Timur - Timur's Lash
Now, some of you might be thinking: "But Beta. There are TEN of them now." or "What about the Sidearm?"
The answer there is simple. There are also only nine Iron Wolves, which the new weapons are named for, who are ALSO missing and have little known about them. The Sidearm is called the "Ironwreath-D" and not named for anyone. The Iron Wolves and their trademark weapons are as follows.
Ashraven - Ashraven's Flight
Bretomart - Bretomart's Stand
Colovance - Colovance's Duty
Deidris - Deidris' Retort
Finnala - Finnala's Peril
Haakon - Haakon's Hatchet
Nirwen - Nirwen's Mercy
Tormod - Tormod's Bellows
Weyloran - Weyloran's March
Nine missing Lords? Nine missing Wolves? Europa/Jupiter? "Rise of Iron" DLC? Call me crazy, but there would almost HAVE to be a connection of some sort. Perhaps the Lords and Wolves are the nine and their guardians (as in bodyguards, not as in Guardians of Light). Perhaps they are simply FIGHTING the Nine on Europa and this DLC is them calling for aid. Hell, maybe the Iron Lords are the Nine and the Iron Wolves are fighting them! After all, the weapon names for the Lords' weapons are all laced with negative connotations (revenge, lie, wrath, etc), whereas the Iron Wolves' weapons are all more positive (mercy, duty, stand).
Perhaps I'm just a nutter with too much time on his hands and an overactive imagination.
Let me hear what YOU think, Guardians!