Their agenda is irrelevant, as is the personality of the people involved, their political affiliations, their haircolour and their dietary and or sexual habits.
And let's hope that others with other agendas and goals will do their bit and release as much or more information as well.
If you only accept facts from sources that are 100% neutral then you end up having to make up your mind without any facts at all, no news outlet, no journalist, no TV station and no editor is able to say that they have 'no agenda', in fact it is entirely safe to assume that anybody that sends facts out into the world has an agenda and wishes to further that agenda by the selective release of the facts that support their cause best.
Wikileaks has been slammed in the past for 'uncontrolled releases', which I thought were actually far more balanced than any kind of editorial control and or selective release.
In that sense they are damned if they do and damned if they don't.
That's not a baseless concern. Wikileaks has an agenda, and it is not simply "transparency".