Same! I thought my account was compromised and they were going to remotely lock or wipe my phone. I was rushing to change my password when I thought about googling it first, I'm glad I did.
From what I can tell, this is a some test on Samsung's end to assure services are working. U expect Samsung will make an official statement explaining but I want to mention it now to hopefully put some of you at ease.
I hope this helps.
@Rydah - How certain are you that Samsung knowingly and intentionally initiated this "test"? I can't say this unannounced, late night experiment did any favors to raising my confidence in the company...