I have 1000's of files in a directory that is used to store the posts Last edit information. eg
[Last Edited by: BassTeQ 20/10/2000 11:51am]

What would happen if I delete these files?
Would it cause any problems, or would it just stop the information about the last edit being included in the post, in which case doesnt bother me.

Thanks.

Yeah it makes a file every time you edit the post, I think if you delete them the post that was edited will return to it's normal version before it was edited.

Does anyone know for sure what will happen?

Why don't you just post a test post, Edit it and delete the edit file and see what happens.