Btw I remember that feature too, in fact that's why I initially reimplemented it
in avian-missing.tmbundle, what happened was more or less the following:
After hitting the new file key equivalent a dialog was presented:
- it has the base-name selected (ready to be overwritten)
- it had the same extension as the current file set
- the folder of the current file was selected
I then
removed it when ⇧⌘N was introduced creating the file directly in the filebrowser and letting me change the name*. But it never was on par with its predecessor and also has that nasty rewrite-as-you-type bug that people reports from time to time.
* also it was relying on assistive devices and applescript and had a few limitations