If you invoke a service that (takes from, operates on, then) sends text to the requestor, WebHTMLView will insert/paste the text in the services pasteboard in non-editable areas. This doesn't appear to be new with Safari 3, it happens on 10.4.10 as well. Easy to reproduce: Build and install/run the SimpleService AppKit example, select non-editable text, invoke its "Capitalize String" service, observe the selected text gets capitalized. This doesn't persist, of course, and doesn't really appear to do any sort of harm. But perhaps it indicates there's some other potentially problematic issue related to changing text that shouldn't be changeable.