I have compiled a list of all the Starcraft II Protoss Units revealed in the PCGamer August 2007 edition. You can read their description. Many old protoss units are back from the original StarCraft. So far the total of Protoss Units is sixteen.

Probe
Zealot
Dark Templar
Immortal
Soul Hunter
Stalker
Colossus
Reaver
Twilight Archon
Phoenix
Warp Ray
Tempest
Observer
Phase Prism
Phase Cannon
Mothership

Zealot
Zealots are the standard infantry [...]

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Blizzard has added a new unit, the protoss phoenix, to the protoss section. The description is accompanied by an animation, voice acting sample and special sound effect.
The phoenix is a swift and deadly spacecraft that is rapidly replacing the older scouts and corsairs in the role of fighter for the protoss. Phoenix patrols [...]

»read more from "Starcraft II - Phoenix Description"