Having just read Squatting Vanity Urls, it seems like whilst squatting is a real problem, it is more inconvenient if you happen to share a name with someone else. To solve this name-sharing problem, would it be beneficial to have a sort of disambiguation page similar to how wikipedia does when there is a name clash? This way, going to
careers.stackoverflow.com/joebloggs could show you all of the Joe Bloggs that have a public CV, with a summary of their CV (similar to how CVs appear in search results) so you can choose the correct one.
This might not be an ideal solution for everyone, but it seems a good approach if you don't happen to get the vanity url first - after all who wants
careers.stackoverflow.com/joebloggs99 as their url?