Here's a preview trailer for the Dragon Soul raid as well as the three 5 mans coming in patch 4.3. It's actually missing music and maybe a voiceover, which is weird so there might be a better one coming soon. But regardless of that it still gives a pretty good idea of the instances to come and looks pretty!

Bashiok has also posted the loot rules for Looking for Raid groups:

As previously announced the Raid Finder will use an altered version of Need Before Greed that provides loot roll bonuses to those that have entered the raid in the role (tank, DPS, healing) that uses those items. Unfortunately the system is currently unable to detect spec, and so this creates some issues for classes that utilize stats that are not "common" to that role.

To help clarify which items you will or will not be able to roll on based on the role you entered the raid in, we have some basic guidelines that we've followed that should help you anticipate which items you'll receive the roll bonus on.

If you're in a raid as one of the below roles here is what you'll receive a roll bonus on:

Tank:

• Agility Leather (for druids)
• Strength plate with tank stats on it
• Trinkets with tank stats
• Trinkets with Agility (for druids)

Healer:

• Any appropriate caster gear without Hit
• Trinkets that trigger on heals or beneficial spells

DPS:

• Mostly everything that doesn’t have a tank stat on it
• Spirit gear (for elemental shaman, shadow priest, and moonkin)
• Trinkets that trigger on damaging spells/melee hits

In some cases we've been overly restrictive when flagging accessories (Petrified Fungal Heart and Signet of Grasping Mouths in particular), and we're planning to modify a couple of those items to be less restrictive before or shortly after the patch goes live.

With Mists of Pandaria our expectation is that we will have the ability to detect spec, and so all of these issues go away for future raids. For Dragon Soul there will be some overlap, though, and it's important you're aware of the loot rules as due to the automated distribution system our support department will not be able to assist with any loot disputes while using Raid Finder.