im probably the last one to be talking about them but I seem to recall something about the "twin lamps" suppose to be in the swamps or something .. for freeing slaves and your suppose to use this "twin lamps code word" or something to enter ..

and what is the real purpose of their organization? will they (or this group or place) exist in elderscrolls online?

The Twin Lamps have only been seen in Morrowind, and they were a minor aspect of the game. (Not a true joinable Faction, and just a few small quests to do for them)
http://www.uesp.net/wiki/Lore:Twin_Lamps

I doubt they would make a return in ESO since they are such a small organization... but I bet slavery will be shown in ESO Morrowind, so it is a possibility.

that's some pretty good news .. ty for this information

this quote here

"Their head in http://www.uesp.net/wiki/Morrowind:Morrowind is Ilmeni Dren, the daughter of Duke http://www.uesp.net/wiki/Morrowind:Vedam_Dren."

was very interesting .. wasn't the Dren plantation 100% all about slavery? .. wow .. having their leaders own daughter involved in the slavery release must have been some serious stuff ..

and wasn't the Dren plantation and its ties to the government vivec and the temple also tied into the morrag tong? .. very interesting ..

Surely they wouldn't be keeping Argonian slaves, though? Not while allied with the Argonians. I couldn't imagine the Argonians signing up to an alliance without demanding freedom for all of their enslaved kindred.

well from what I understand the telvanni are not taking part in the war at all .. keeping themselves separate from the alliances all together. which makes sence .. but yes I do agree .. it would seem a bit strange having both argonians and khajeets sitting in their towers while they are all at war ... not sure how this will fair ...

House Telvanni would likely keep all their slaves, regardless of any alliance.
But it doesn't seem like their territory is going to play a big role on the map. (so far)

I know they're their own group within the Dunmer, but why would the Argonians support an alliance with the Dunmer while any Argonian was a slave in that nation?

It doesn't make sense to me.

Argonian slaves could be purchased from the Telvanni or exchanged for members of other races, and then released. With the war going on there'd be no shortage of opportunities for nabbing enemy soldiers.

consider the source.

Same with House Dres.