This is a draft of the invite I'd like to place on people's pages
Thank you for your contributions towards improving the categories of Wikipedia - they have not gone unnoticed!
Because of your interest in helping out with the categories I thought you might like to know about the WikiProject I have set up for to help organise the categories of Wikipedia:
The members, of course, will form and solidify the purpose, rules, officers, etc. but my idea (to kick things off) is to establish a group of us who will take responsiblity to organise the core categories of Wikipedia and see that the whole namespace is managed so that it can grow and need less on-going maintenance.
Then please feel free to comment on what I've proposed so far on the talk page: Wikipedia talk:WikiProject Categories.
Thank you for your time. Even you don't want to take part - keep up the good work!