Social identity theft - protecting your personal brand

I recently attended a talk given by an OpenId foundation member. I would not say here where and who gave the talk. What I came to know is that the big web-based identity providers (IdP) such as Google and Yahoo! have embraced OpenId for almost couple of years now and they would want you to use your id/account as many places where open id is supported. Facebook wants you to do the same but their protocol is very proprietary. Anyway, this is good news!

1. This helps a lot in increasing user registration at a relying party (a social media application) web site because users can sign in using their OpenId. 
2. It also helps those folks who want to use OpenId to sign in where ever they could because they don't want to keep track of and maintain various social identities and profiles at various social media web sites. 
3. Lastly it helps in further service authorization and sharing of content using OAuth.

However, this also makes these folks vulnerable to social identity theft. If your social identity is stolen, not only you are vulnerable but your social graph might be vulnerable too (without any reason). This is more dangerous.
I came across an article "How to Combat Social Identity Theft and Strengthen Your Online Personal Brand" where the author recommends creating a separate profile and identity at each social media site . This is like having a separate password for each web site...hard to remember and maintain but it restricts the vulnerability to a single profile/identity/website if stolen. Some folks even provide a service to manually go and create profiles in your name at some 150 web sites! Indeed, what guarantee they give that they won't misuse this information, disgrunted employees could be found everywhere right! And finally there are tools like KnowEm which automate the process by helping find availability of the username at>350 websites and also help create profiles (with subscription service). Many other such tools are listed here.

I would think that one should carefully use identities maintained by the big guys. I would also keep more than one OpenId handy to use at various social media web sites so if any one of these is stolen, at least the vulnerability is contained to only those sites where it was used. However, indeed there could be a better solution...looking forward to your comments, thoughts and suggestions.