If Wikileaks is more important than the possible sex offence (as it probably is) then you should ignore info about the Assange's personal life.
The above equation seems very wrong. A better one would be to compare:
Wikileaks is probably more important, however if you choose to ignore the court case, your probable level of ignorance about it is much higher.
Given that I am not remotely interested in a single crime that may or may not have taken place between two people who I will never meet (and neither should anyone else be, unless they avidly follow all rape stories that take place anywhere in the world), I would say that the comparison still comes out strongly in favour of ignoring the case and focusing on Wikileaks.
From Nate Silver of FiveThirtyEight: A Bayesian Take on Julian Assange.