The help guide suggests:
The Cut, Copy, and Paste commands in the Edit menu … Copy text from a word processing document and Paste it into a reference. If it is important to paste the text along with the fonts and text styles, use the Paste with Text Styles command in the Edit menu. The regular Paste command does not include font, size, or text style information when pasting into EndNote from another program. Avoid pasting unwanted fonts and text styles into EndNote references because those fonts and text styles will carry through into … bibliographies.
But in practice when you you cut and paste from Word 2007, the formatting is retained regardless of whether you use the ‘Paste’ or ‘Paste with Text Styles’ options.
Greg Fry
Faculty liaison librarian