Win7 64bit takes up to as much as 1.5GB for itself let alone leaving RAM for other apps and services.
The advice is good, that there's currently little point in installing 64-bit on a 2GB system. But the statement that "Win 7 64-bit takes up as much as 1.5GB for itself" is not true; it takes up no more memory (or certainly not significantly more) than the 32-bit version.
There are a lot of misunderstandings about memory usage in Windows 7, particularly because - like any good OS - it grabs unused memory for cache usage. But that memory is still free for applications and will be released as soon as it is needed. I prefer my OS to use as much of my memory as it can, in an intelligent way; no point in buying RAM for it to just sit there heating the computer.
The only reason to use 64-bit would be if the laptop could accept more memory and there is a chance that at some point in the future you might want to supplement with 4GB or more. If that's not the case then 32-bit is the route to go.