Hi
I used easy populate module to deal with this. If you want the same attributes adding to all pages.
Add the attribute to a couple of categories first then download the models/attributes file using easy populate.
Open the file in your favorite spreadsheet. compare the attributes files between the categories you have updated against those you have not updated and then just copy the differences. upload the new model/attributes file using easy populate.
I adding a new attribute with a text field to my shop. almost 20,000 products updated in under 10 minutes. Much quicker than using the admin and updating each category at a time (! have over 500 categories)
hope this helps someone.
Kevin