Google (or any other search engine for that matter) will see the same thing as a non logged-in user. Unfortunately, there currently isn't any secure way to have google see the post content, but have users be redirected since it would be easy to spoof user agents etc. to pretend that you are google and not a normal user.
It might be possible to add a feature which would show a fairly trimmed down page to search engines, maybe only containing the post title and excerpt. Is that something people would be interested in?