One of the defining features of Timeline is that it’s simple to travel back in time a few years to see wall posts and old pictures.
Even if these posts and pictures have always been public, the older stuff was likely buried before. With Timeline, they’re just a click or two away.
Once you activate Timeline here, you’ll have 7 days to review all of your old stuff and change privacy settings accordingly. If you decide that you want to make any old stuff private, go to your Privacy Settings and click “Limit The Audience For Past Posts.”
If you want to see what your new profile will look like to the public (or to specific people), click the Cog symbol below your new cover photo and click “View As…”