Well i do agree with all that was posted, but i think that, based on the chronology and the possible separation from the swarm (since Kerrigan is not the Queen of Blades, via artifact use), and i do believe by the comments of Zeratul once he knows who could save them "If only we had known.".
I speculate that Kerrigan after the re-encounter with the Zerg biology (as hinted by the evolution system described on HotS) she might not have enough psi performance, lets put it like that, to unite under her such large amounts of consciences (a medium zerg army she might be able, lets face it she is powerful) but the full girth of the zerg (dozens of conquered/infested planets, billions of larvae) its a lot of voices, so i guess she will have to be though/trained/enhanced by the Protoss Preservers on how to interact/control/unite all those voices into her and how to resist/counter the hybrid/Dark Voice influence over the broods.
TLR -> WoL: Saved from psychotic fixation on destroying everything. HotS: Reunion with the full zerg biology, doors opened to full control of the Swarm. LotV: Training and ascension of her Psy capacities in order to lead the full zerg onslaught against the Hybrids and their masters.
Also the standard battlecruisers with all the abilities in the campaign are so powerful that i guess they count as a ultimate unit.
Actually Legacy of the Void will be all about Zeratul and the use of diplomacy to unite the Protoss... which I hope is way more exciting than it sounds.
The only diplomacy I'm fond of is war. And the best diplomat is a good ole psi blade.
[Edited by AdmiralAckbar, 9/1/2010 4:33:43 PM]
Oh... Then I am stunned... but I still believe that the Protoss have to be somewhat related to the maturing of the Queen of Blades V2.0
Maybe. But if it will be, we'll be the Protoss. For now Blizzard has us all guessing.