As it stands right now, the images are not verified to be real or anything. But at the same time, Samsung has not commented on the existence of a new Galaxy phone one way or the other. Normally if a picture of something that isn't real is floating around, companies are pretty quick to come out and say that it is fake.
If the pictures are real, then the metal exterior is going to signify the death of the plastic Galaxy phones on Samsung's past. That was one of the big reasons that they couldn't ever come close to killing the iPhone, people want a product that doesn't feel like a cheap toy. In my opinion, that is probably the only real reason that more people would prefer the iPhone over the Galaxy series.
If you are super eager to find out all about the phone for yourself, there is a British retailer called MobileFun who is now offering pre-orders for the phone, which is for now being called the "Galaxy Alpha". The pre-order costs $939 and doesn't come with a SIM card. The site says that the Alpha is going to have a fingerprint scanner and a 12 megapixel camera, which are two things pretty similar to the Galaxy S5.
SamMobile is a Samsung rumor site. They released a few images a while back that apparently showed really early prototypes of the Galaxy Alpha. Those photos only showed images of a black version of the phone though, and these newer photos that have leaked show the phone in white. This means that Samsung may be planning to offer the Galaxy Alpha in both white and black like the previous Galaxy phones. So far though, no Gold pictures have popped up. Everyone thought they might do that.
The new Galaxy Alpha is so far expected to run on Android 4.4 "KitKat", and it is also supposed to start at 32GB and go up from there. On the Weibo page that leaked the pictures, they claim that the Galaxy Alpha will come in both 4.7 inch and 6.7 inch sizes.
Samsung hasn't said anything about the official release date of the phone, but SamMobile originally reported that the phone would be officially announced on August 4th. Obviously, that was yesterday. But a few days ago they changed it and said that it would now be announced on August 13th. I guess we'll see!