No, really?
And that doesn't give it any excuse to be paging out with a few tabs in Safari or Chrome (whichever I used at that time), Skype, Calendar, iTunes, and Finder open. I get away with much more than that with 4GB on my Windows desktop.
This is a really wild load of complete BS!
OSx will utilize the memory available for what is necessary both with open applications and caching reserve memory for recently closed apps. With the high speed SSD as well...even an occasional Page Out isn't noticeable to most
Guaranteed the memory management of OSx is as good or better than any iteration of Windows 7 or earlier (I'm not at all familiar with Win 8). However, a few tabs on Safari (possibly 150-200mb), Chrome (150-250mb), Skype (maybe 500mb---very rare that high), Finder ( typically <50mb)--- and iTunes, pending library size anywhere from 300-1500mb of RAM. A grand total of 'maybe' 2GB active use RAM in your scenario posted WITH both browsers open (which you don't do, right?). With OSx, the more RAM available, the more it will use inactively or for caching purposes. If 4GB is what you have, it'll manage the memory appropriately. Today..and most likely for another couple years...4GB will be more than appropriate for casual computing.
When you get into video and heavy, RAW Photo editing, RAM can be a great thing. Huge PDF files, spreadsheets and massive data libraries or audio collections ( in iTunes ) benefit from more RAM as well. The OP will be
just fine with 4GB
Not sure why some post this cockamamie BS, but keep your ears and eyes open. Four GB of RAM in the current state of OSx (Mountain Lion on a modern machine) as others have Also pointed out, is plenty!
J