Sounds a little alarmist, I know, but yes beware. The thing is, I don’t want to install 64-bit arch on machines that have less than 4 GB of RAM. It doesn’t make sense. Not only is the execution theoretically marginally slower, the files also take up more space. When building virtual machines, it begins to make even more sense to install 32-bit.
Debian’s new fangled (probably been out for a while now) multi-arch installer will install a 64-bit OS if the CPU supports it. So beware. Either download the 32-bit installer or perhaps there is some switch to force the multi-arch installer to install a certain arch. I don’t want a multi-arch CD laying around. The risk of installing the wrong arch is too great.
It’s good I noticed before putting this server into production. (Goes off to install 32-bit Debian…)