It is known for sure, that they are developing at least two separate productions,
one in dark fantasy universe (some Witcher game for sure) and some RPG in other setting,
look at CDPR career pages...
I hope for (paid) expansion for The Witcher 2, because it can be expected in shorter time
and technically this game is good enough to be played again with minor improvements or additional story only;
there is no need for new engine, etc. - it can't be better if has to be ported to available consoles.
I wouldn't want a second expansion pack. TW2 is, allowing for some loose ends, a complete story. If they produce anything more for TW2, I hope it's a construction set.
I don't agree...
There are many possibilities to extend the game without compromise to the story.
As long as Triss is not abducted by Letho there is no hurry,
Geralt does not know who the assassin is, where or even how to find him,
we are seeking opportunities, so any lead is worth to be explored at the moment.
For example troll near Flotsam (or someone else if we decide to kill him)
can repair the bridge as asked (when we go to do something else at different place),
so later someone from the city can send the witcher with message to village at the other side
and while being there we can help people, do quests, learn something more about the world.
Perhaps it would have nothing to do with main story, but perhaps it would be good for the game,
as player will gain completely new view and insight about Northern Kingdoms.
Other idea is to explore some part of the way from Vergen to Loc Muinne.
There are mountains, canyons, caves, monsters and treasures to be found, quite an adventure.
Main task would be to complete the path in lets say a week (pressure of time would be new to the game),
but in the mean time we can do as many quests as possible - heroes have to earn money and trust
to get food and place to sleep in 2 or 3 taverns and villages at the way.
Last and smallest extension that I have to suggest:
It would be nice to have some side quests at Kaedwen camp side of the mist while following Iorweth's path,
and similarly something more to do near Vergen when we decide to help Roche - there are places we can visit,
but they have no real meaning, they are not used in these versions of the story.
Wouldn't you like to see something like these?
This is just an imagination of a single player... And designers probably have many more and better ideas.
I would like TW3 also, but later, after next expansion. This game can show us much more...