Saw this over on Reddit; 

@LikChan It's DEAD SILENT. Quieter than the new slim 360's.

— Albert Penello (@albertpenello) August 16, 2013

xbox one is dead confirmed?

Can you add anything to a thread?  Always some type of negative comment towards XBONE.

OT : I hope it is that silent.  Sick of hearing the consoles all the time when the have been on a coupe of hours.

yes i can. i always add negativity according to you

That's cool but the sound of the 360 slim is good enough for me, I don't even notice it.

Made me laugh.

It is much bigger than the slim. It likely has much better airflow than the slim to dissipate the heat. it will produce a lot more heat.

I'm skeptical, but it's definitely possible if engineeered right. My pcs much more powerful then slim and is quieter because of airflow. If its engineered poorly you get rrod. 

Considering the size of the fan they've put in the console I'd be shocked if it wasn't quieter. It looks bigger than most PC case fans.

That's good news.

The thing I'm hearing is that most people accidentally turn it off the first time, cause they didn't realize it was one. So quiet, no vibrations.

It's the way I like my electronics to be.

It bloody well better be.

My 360 slim sounds like it's trying to escape gravity.