So, there's been some debate thus far on the subject of instancing and dungeons. My first MMORPG was actually City of Heroes (I'm not a super hero fan, but that game was/is FUN ^-^), and everything was instanced. I've also played games like EQ2 where the world is zoned, but not instanced. I can't count the number of times I've been in places like RoV and merged my party with another (party sizes allowing, of course).
Both types have positives and negatives, and I'll refrain from posting them here since I'm sure most are familiar with them (and the posters who reply to this thread will likely reiterate them anyways). My thought on the matter is how difficult would it be for SE to implement BOTH setups for each dungeon?
What I mean is that when you walk through the entranceway to a dungeon (or cavern, or tower, or lair, etc), it gives you a choice: "Launch private encounter? {Yes} {No}" Selecting yes gives you a private instance, while selecting no deposits you in the open world version of the instance.
As the forums have shown, we have some rather strong divisions in how players feel the game should be structured, and a part of me wonders if extra effort to appease both sides in matters like this is worth the effort.