Following a friends advice, I have just replaced a 64bit version of ubuntu with the 32bit version on my desktop.
My desktop is a 2yr old dell with 1GB RAM.
Suddenly, it seems like I am using almost 50% less RAM during my usual workflow.
Could someone explain why this would be the case? Is it normal, or was my 64bit installation hosed?
Check which processes consume memory. Htop is a good program for this: http://htop.sourceforge.net/
jeffamaphone is correct. Between 64 bit pointers being twice as wide and needing to load duplicate 64 & 32 bit libraries if you use so much as one 32-bit only application (such as flash) you will see outrageous memory usage.
I do not recommend 64 bit workstations until exceeding the 32 bit memory limit for this reason.