Clipping files in Snow Leopard have gained significant features. First, they now work with Quick Look. Second, you can open a clipping file and actually select a portion of the text to copy. Finally, they have a fully-functional title bar, so you can Command-click (or Control-click) the title to see the full path.
[robg adds: In 10.5, you actually could copy text from clippings, but the selected text didn't highlight, making it very hard to use this feature.]
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