readahead-gen looks like something that some folks would appreciate, for example I'm planning to take a look at doing a readahead package for KDE-centric boxes sometime. It would be nice to include the script in the readahead package (probably as non-executable %doc so that it wouldn't create extra dependencies).
The script has been renamed to readahead-check and you can found it in FC6 in /usr/share/doc/readahead-1.3/readahead-check. There is also the /etc/readahead.d directory where you can store your custom files (e.g kde.later or kde.early). It's not problem if your lists contain duplicate files -- readahead ignores duplicates now.