SCOTUS Trump's Travel can go into effect
Breaking... they ruled 7 to 2 to allow it to go into effect pending appeal.
EDIT: I meant to come back and add commentary and thoughts!
I agree with this ruling. Note this is not a ruling just a temp green light until they can make their ruling.
As to the order itself. Presidents have the general authority to not allow certain classes of people from entering. That can not JUST be on the basis of race or religion. However, Islam is not just a race(ethnicity) or religion, Islam is also a socio-political moment. Add to that there are nations on the list that are NOT Muslim (but I do think adding those was more to say it was not just Muslims) and many Muslim nations that are not on the list. And that there have been terrorist acts by or influenced by Muslim immigrants in the US and UK and elsewhere I see the EO as legal and I believe it will be upheld.
[Edited 12/5/17 5:16am]
"...if you don't have a sword, sell your cloak and buy one..." ~ Jesus Luke 22:36