Wikileaks is about trying to implement the right to know, the right to inform and source protection via technology. This is laws[1] that in Sweden[2] is part of the "constitution" via the freedom of press act and the fundamental law on freedom of expression (free speech). If more countries had similar laws, Wikileaks would be unnecessary. If you don't agree with or understand why these laws exist, then of course your view on the necessity of Wikileaks might differ.

Wikileaks, just like laws on rights and freedoms, will sometimes facilitate the distribution of, for governments, "problematic" material. Does this mean we should remove these laws and/or outlaw Wikileaks? Not in my opinion. Of course there will always be some limitations.

Nothing stops government and organizations from protecting their information in the first place. Wikileaks doesn't pick what information they get access to. If someone in your organization is leaking your most inner secrets, you probably have more serious problem than than the existence of Wikileaks. Also the public nature of Wikileaks distribution model means that intelligence agencies are free to do all the operation security analysis they want when something is published.

[1] http://www.meddelarfrihet.nu/freedom.php?lang=en

[2] This is why Wikileaks is hosted in Sweden.