When open sauce turns sour

Talking about the limits and scope of open source branding, there was a v.interesting little article in the Sunday Times yesterday about Wikipedia - the king of open source apps on the net.
The article points out a battle going on at the mo involving hackers adding spurious entries into the community-based encyclopedia and thus breaking the whole spirit of open source. Amusingly it seems that a number of mandarins (or their geeky researchers) from both Whitehall and Capitol Hill have been hacking the system and adding in damning, and some times humorous, descriptions to their opponents.

The point: this is a great illustration of the lawlessness of the net and the fact that OS culture is wide open to abuse. So what's the impact to open source brands? Does the presence of wreckers mean the death of the notion of a truly open brand?
I think this may well be a detail - however it's worth considering . . .