Two more Corrupted Rogues are taken out by the Immolation Arrow, which creates a miniature Firewall wherever it hits.  The Ice Arrow is selected next, this potent skill freezes enemies solid after a few hits!  She successfully freezes a zombie and a rogue, demonstrating that the enemies sit frozen for some time.  Zombies are effected for longer, perhaps because they are not as powerful as the Corrupted Rogues.  The final upgrade of the ice skills is shown, called the Freezing Arrow, which combines the Cold Arrow, the Ice Arrow, and an explosion which splashes the damage and effect.

We change locales to Act II's Lut Gholien, still with the Amazon, but this time carrying around a spear.  An unknown skill is displayed in the status bar, a skill that might be her Jab skill for the spear.  It also shows the true transparencies of walls, where Diablo had only dot-dithering.  As the Amazon enters the Palace in Act II we get a good look at the cutaway technique where buildings are entered and the ceiling is removed so you can see the action.

As the Amazon descends the palace's spiral staircase we get another look at the seamless change of levels, the screen changes in a mere second, without any real breaks in actual gameplay. 

The Paladin

With a transition the Paladin is finally displayed, but when he appears his skill tree window is open.  The window for skills presently displayed are Auras, and the player travels through each icon on the windows, showing us what they are.  Each icon on the skill tree has to be allotted a certain number of points before the next one is highlighted and available.  Here is a rough list of the skills in the Auras tree, in the order that they appear:

• Resist Fire: Aura that resists fire damage.
• Resist Cold: Aura that resists cold damage.
• Resist Lightning: Aura that resists lightning damage.
• Salvation: Aura resists fire, cold, and lightning.
• Consecration: Bonuses for caster and nearby players.
• Sanctuary: Creates a barrier against undead.
• Shepherd(?): Aura.  Paladin absorbs target's damage.
• Thorns: Aura that returns damage to attackers.
• Fanaticism: Aura boosts overall speed.
• Defiance: Aura allows quick return strikes.

The next skill tree shown is the Healing and Undead tree, with these as its skills:

• Block: Increases chance of blocking (passive).
• Bestow: Heal others.
• Pray: Heal yourself.
• Cleanse: Reduce the duration of poisoning.
• Cleanse Other: Reduce poison duration on others.
• Retreat: Reduces damage and steps back (passive).
• Blessing (?): Remove a curse.
• Purify: Cures poisoning.
• Ressurect: Brings friends back to life.
• Meditation: Bonuses for casters and nearby players.

The final skill tree shown is the one for Combat skills:

• Sacrifice: Speed and bonus damage.
• Zeal: Single-motion attack and advance.

Unfortunately, that was all the combat skills it showed us before the next transition.  I did notice an icon that bore a striking resemblence to Holy Bolt, and I suspect that the Paladin has this one as well.  I did my best to make sense of the blurred words, and the following list is subject to change by Blizzard in future builds of the game.