DA:I MP took a hit to the user-base when Neverwinter went live on consoles but bounced back in full within two weeks. I suspect ESO going live on consoles will have a similar effect. It might take a little longer to bounce back from ESO because everyone going to ESO had to buy the game while Neberwinter pulled in a lot of impulse d/l's.
In any case, I'm fairly confident we'll see two more solid MP dlcs for DA. One with a new faction, map, and 3 new characters. One with a new difficulty, 3-6 new characters, and hopefully another new map. Mind you, this is just pure speculation on my part but based on how long Bioware said they'd support it and how long Dragonslayer took to get released I think my guesses are reasonable. If we get more, fantastic! If we only get a new faction dlc, I'll still have gotten everything I expected from DA MP.