Varied, because otherwise you risk creating a lot of duplicate content, especially when you end up submitting to sparsely-populated categories where you could be the only submitter. I get a lot of directory submissions which use the same text as the website's homepage. In theory, you could knock your own index page out of the SE's index by doing this, if you copy enough text and the directory page is more important and was indexed earlier than your own.
I've got to agree with that, I don't like it either. The best approach is semi-automatic, where you use a tool to help you fill in the forms. There are a few Firefox plugins for this. This saves you copy-and-paste time, but you don't miss out the essential step of visiting the submission page and checking the guidelines, and also varying some of the fields.
AllSubmitter seems to suggest that you can use it in a semi-automated as well as a fully automated way, so there are probably good and bad ways to use this tool.