True that my laptop runs 64 bit Win 7 but the only 64 bit applications are the accessory apps included with the operating system. Every program I've installed is a 32 bit application.
I remember the link and reread it to refresh my memory. I didn't see any reason other than personal preference. A second reason given was that 64 bit software is the direction the computer market is moving to but that is more an observation than a reason.
The first reason has merit. For example customer desire for variety forced the automaker, Ford, to add exterior colors to their production pallet.
As best as I can determine the main benefit of a 64 bit operating system is a 64 bit system can manage more RAM memory than a 32 bit system. 32 bit systems limit RAM allocation to no more than 2 GB of RAM per process, no matter how much real or virtual RAM is available. The 2 GB per process limitation does not exist with 64 bit systems.
On the other hand 32 bit systems split RAM memory into smaller chunks than 64 bit systems so you are less likely to encounter "low on memory" or "out of memory" warnings in a 32 bit system when both systems have the same amount of RAM memory.