First I'd like to say I'm thrilled to hear about the Elder Scrolls Online project, and wish you all the best on your endeavors. I'm sure you'll do an awesome job

Just wanted to share a few bits of useful info in designing an MMO. I bring with me 10+ years of MMO experience.
- Players want innovation.
Players want to see something "cool" to grab them from the get go.
- Players want a polished experience.
From the login screen, to the Game Engine environment, players want a compatible to all / rich experience. A "Clean, Feature Filled" Ui.
- Players want to customize their character, to give them the "avatar/hero" they're looking to create.
Give the player the ability to customize his/her character to make him/her *unique*. Try to avoid giving 2 players the same looking "Tier" gear (big turn off for players). When you have the ability to customize the style of your character, you'll be more attached to it. Some MMO's give the ability to dye your Armor, or show your Guild Emblem.
Furthermore, Player Housing gives another huge plus to Customization. Players would love to customize their House, with rare trophies and use it to sell equipment. This feature will further enhance the MMO experience, to give players even more.
- *Very Important* Design the world in a way where it feels "Massive"
Players are looking for a "Massively Multiplayer" experience. One of the big disappointments with other MMO's was the porting all over the place. At one point I'm adventuring at a dangerous swamp, the next second I ported to the middle of a city, and the next I port to another town. (No sense of adventure) That's a major turn off for a player who's looking for an immersive experience.
The world has to feel "Massive". Going out for a quest, or hunting of any sort, should feel like an adventure. This is debatable, but in my experience, porting all over with no cool down defeats the purpose of a real adventure.
- Design boss encounters to feel like an Epic encounter.
When you form your group/raid and venture out to kill a Boss, your looking for an Epic encounter. A failed design was when the End game boss was 2-3mins from the main city (WOTLK - ICC). That design was a very bad one in my opinion. When you think your going after an end game villain, you'd think you have to spend some effort to reach it. Not flying for 2-3 mins, zoning in to find him right in front of you x) No immersion. In the other hand players don't like to spend too much time clearing trash to get to the boss. The main point being, players want an Adventure experience and not a spoon fed boss. Think out of the box. Put yourself in an Epic Adventure scenario (seen in adventure movies).
- Players want a "Massively Persistent" faction war.
This is essential for a sustainable MMO design. This war should never "reset". Imagine you put together a group of friends to capture a Tower or a Keep, excited that you achieved this and claimed it, to be Reset by a timer? Players will not be interested in taking part if their efforts will be reset.
Again I used the term "Massive". Its essential, the world conflict area has to feel massive. Traversing forests / terrain reaching the Camps / Towers / Keeps should feel like a real adventure. (Minimal porting please

- Design an enjoyable experience that could serve 2 million players+ from the start.
Primarily, its important to design an enjoyable experience, though you have to keep in mind population limits. You dont want an area over run with players
A funny experience with an MMO I tested was when 1million+ players were trying to login at the same time (Beta tests and release), that totally destroyed the login servers 
- Easy to get into, difficult to master.
This is essential in design. The design has to be approachable, yet will take a skilled player to master.
- Innovative Quest Design.
Players are looking for creative quest designs. For example, you could accept a quest to kill 4x Rats... *boring*. Or you could be involved in a creative story involving retrieving a stolen heirloom. Bethesda's Elder Scrolls are the best example in the gaming industry in designing quests.
Hope these ideas are useful. Cant wait till we can test!
Wishing you all the best!
