The trailer's narration is puzzling. All previous indications had been that the story was going to focus on Rhobar III's imminent invasion, but now it seems he may be but a distraction from the real enemy, this unspecified ancient evil. While having the Sleeper or the Undead Dragon return could make for an interesting twist if done well I'm hoping for an entirely new antagonist.
Also worth noting is that the trailer states "welcome to the world of Arcania", providing further evidence for the theory that Jowood is using the fame of the Gothic series as a starting point for launching an entirely new, unrelated series they have full control over (some rights currently have to be licensed from Piranha Bytes, including the Gothic trademark).
The camera puzzles me. They have previously shown an overhead camera, but the more recent footage seems to favour this strange floating camera, so it's not clear whether both are available or the camera angle has changed during development. It would be nice to have the chase camera as an option, but its omission wouldn't surprise me.
The golems look great (as do all the other creatures), but what troubles me is that the player can seemingly damage them with a normal battleaxe, whereas in the previous games they took little or no damage from anything but blunt weapons or magic (in the case of fire and ice golems the magic even had to be of the opposing element in order to hurt them). While it's remotely possible that they made this concession for the purposes of the E3 demo it's much more likely that this is yet another way in which Spellbound has watered down the gameplay.
The new rune system with cooldowns is an interesting step. If the runs have individual cooldowns rather than an overall one and don't consume mana that would open up the potential of chaining several effects together in rapid succession, something that was difficult in previous games without first building up a sizeable mana pool.