Okay I am just having one of those days. I am documenting our
environment and I noticed that WSS 3.0 I not listed in Add/Remove
programs. Last year we did a database upgrade from SharePoint 2003 to
MOSS 2007. We currently have SP2 installed but when I go to Add/Remove
programs, I do not see WSS 3.0 listed on our farm but it is listed on
our environment that was not upgraded (just installed MOSS 2007 out
right).

This is what I see
MOSS 2007 Version 12.0.6425.1000

We are running both MOSS 2007 and WSS 3.0 in our production environment.
Is this normal/to be expected.