Yes, yes, they forgot to update the readme file. They were in a bit of a hurry for the security patches.
Look at the version.php in the wp-includes directory. That’s what they normally update. Better yet, look at the bottom of your admin screen. It’ll show you what the real version is.
Also, there is no database update on this one. Not every upgrade updates the database. In fact, you don’t even have to visit the upgrade.php page, ever! All you have to do is go to the wp-admin page as per normal. If it needs a database upgrade, it will tell you so explicitly and give you a link to do it. WordPress is smart like that.