Alex,
We have discussed this feature with the team and it requires to bypass some of the security in WordPress. I believe this is not good decision, as it can bring into problems you and other blog owners.
I thought of another way of handling this:
– plugin will have option to define default role assigned to the user authorized via social network. There are currently two of them: one is the “Subscribed” (default from WordPress) and one custom from the plugin “Social Subscriber”
– later you may search through users and find with role you defined in “Users” page
Why it is better to keep user registered in the system:
– in the a few next releases we might introduce nice analytics over the users on your blog
– you may contact any of the users who registered on your site
– and it can be used to send info about your products, new blog posts, etc
– and certainly, users are the ones that help blogs to grow
What do you think about it?