It is not news. There is ice on Mars, we know that. The sun shines on Mars, we know that too, so all we need to do is put the two together — there must be water. All you have to do is have the instruments to find it and know where to look. The same principle as looking for where you left our house keys.
Except NASA have no found any water on Mars. No. They claim to have found chemical evidence that gives a strong suggestion of water mixed with salts.
So there is ice and sunlight, there must be water, but they may be closer to finding it, but we have not found it yet. We’ll just have to make do with the picture from Twitter.