I have 4gb of RAM and, upon boot, with nothing running, my memory usage is at 1.3 GB. I have very little loading at startup. Trust me, I've checked.
I attribute it to the Superfetch feature as I run many memory intensive applications on a regular basis, AutoCad Architecture 2011 being but one, CS5, for goofs (thanks, Arc for the sig
), being another as I am a nerd at heart and could afford it a few months back. I run the full Office 2010 suite as well with Outlook always running (my PST file is over 2 GB).
Whenever I start an app, the memory is redistributed instantly. I go by the "Hard Fault" count in Performance Monitor. Even with the apps I run, the Hard Faults never get to a level of concern.
Windows 7 is very adept at managing memory. I no longer pay attention to it.