@ Fai I don't doubt the Unohana stuff, she will definitely kick some ass in the upcoming battles. And yea the 0 Squad seem like righteous arrogant pricks, but I disagree that they couldn't give a damn about the SS. More like they are simply doing their jobs in ensuring the safety of the Soul Palace. It would dishonor, and disrespect the Gotei 13 if the 0 Squad came to the rescue every time a crisis occurred in SS, like they are a bunch of infants who can't even feed themselves without the proper supervision. Honor, respect, and duty are highly regarded qualities in the Japanese culture, and the 0 Squad are not exempt from adhering to those beliefs.
They can't do anything without first obtaining instructions from their boss, the Soul King, and once he/it saw that it was necessary to intervene, they then made their move. The single most important rule in Bleach has been shown to be the absolute protection of the Soul King. So again, they were just doing their extremely crucial job of obeying the will of the SK.
I seriously doubt they have bad intentions planned for Ichigo and Co. or else why would the aforementioned captains not at least make an attempt to stop them from being led to their doom. Obviously some of the older captains have, albeit strained, relationships with members of the 0 Squad. I find it highly unlikely that they would willingly allow Ichigo, and others to be taken away, just to be killed or imprisoned without first putting up a fight.
If they are as evil as you think they are, then why not just swoop in and take who they please, instead of conversing and explaining why They need to heal them instead of Unohana. They are obviously powerful enough to do whatever they want, so it makes no sense for them to show enough respect to take the time to inform the captains as to why they are being taken away, if in the end the 0 Squad are really just evil.
And lastly, I am confused here? I don't understand how some people think it could be Urahara on the other end of the line in Hueco Mundo. A few chapters back, they said that Urahara had reported in to let SS know they were okay, but was unable to speak to anyone directly. This leads me to believe that they are in fact, not in control of the situation in HM. That combined with the panel of the sword pointing at Urahara's throat should mean that it has to be someone else, right? I mean, why would Urahara point a sword at his own throat, and it seems likely to me that the person on the other side talking would be the one who killed Kirge. Is there something I'm missing?