Did something in particular change so they no longer needed her testimony, or did they finally accept her argument that she already told them what she knew and had nothing more to say?
Edit: Oh I didn't see that the Assange grand jury was dismissed today!
"the court finds Ms. Manning's appearance before the Grand Jury is no longer needed, in light of which her detention no longer serves any coercive purpose."
It also makes the reasonable point that the Assange grand jury had been dismissed, but IIRC (and it's only been two or three hours) the court's statement was clear that incarceration to compel was not necessary. (Probably motivated more by the grand jury's conclusion than the suicide), but if you'd like to tell all of us what you think they said, that would be super!
Edit: Oh I didn't see that the Assange grand jury was dismissed today!