I got the 2.3/256/8 retina MBP right now and I have been reading the threads about ram and the majority recommend 16gb. Well here is a screenshot of my just woken up RMBP. I got chrome open with 4 tabs, itunes and the mail. You can see I am only using about 2gigs of ram. But its an illusion. I noticed that when I use my RMBP for a day its sucking my memory like crazy. Mail, Chrome and iTunes combined can already use more than 4gigs at the end of the day. And if I run a few other apps like a video player or a program to download some torrents. At the end of the day it usually looks like: Free RAM: 200mb wired: 2gigs active: 4gigs inactive 1gigs page outs: significant Roughly. I barely use any programs at all. That means I have no room whatsoever when I want to use the heavy hitters like virtualization or photoshop. Yet on my old MBP13 (early 2011) 4 gigs was more than enough for what I am doing now and virtualization. Before I had a laptop with 2 gigs and that was also enough. Over the years my usage hasn't changed at all. Do I need to get 16gigs? Btw I didn't notice a slowdown whatsoever when it was paging out. Cause I think the RMBP might be the one. The one that I am going to use for 3-4 years.