A 24-year-old graduate student at the California Institute of Technology named Virgil Griffith (hacker name: "Romanpoet") has created a program called "Wikipedia Scanner," which matches IP addresses of Wiki editors to the names of the individuals or groups to which those addresses are registered. So, yes, you can still edit your own profile (as so many people do), but prepare yourself for the humiliation of being outed...
Among those undercover editors already dragged into the light of day is the CIA. According to the BBC:
On the profile of Iranian President Mahmoud Ahmadinejad, the tool indicates that a worker on the CIA network reportedly added the exclamation "Wahhhhhh!" before a section on the leader's plans for his presidency.
A warning on the profile of the anonymous editor reads: "You have recently vandalised a Wikipedia article, and you are now being asked to stop this type of behaviour."
Other changes that have been made are more innocuous, and include tweaks to the profile of former CIA chief Porter Goss and celebrities such as Oprah Winfrey.
When asked whether it could confirm whether the changes had been made by a person using a CIA computer, an agency spokesperson responded: "I cannot confirm that the traffic you cite came from agency computers.
"I'd like in any case to underscore a far larger and more significant point that no one should doubt or forget: The CIA has a vital mission in protecting the United States, and the focus of this agency is there, on that decisive work."