What is with all the lock screen security flaws these days. Apple just patched one on the iPhone, and now comes another Android flaw. Actually, this flaw is with Samsung's TouchWiz interface that runs on top of Android.
As you can see in the video it's not very easy to exploit this flaw, but it is possible to get past the lock screen and take command of the phone. You have to be quick, but it is possible. It involves being fast enough to get voice search going in under a second, then searching the Play Store and installing the right app.
Samsung will no doubt figure out a way to patch the flaw, but we've see several of these lately so I'm wondering who is handling security at all these companies. The chances of falling victim to this flaw is small, so Samsung will probably patch it before it becomes a problem for you.