Visio 2003 supports two types of comments: Shape ScreenTips and Annotation.
Shape ScreenTips is the older of the two and associates a comment with a shape that appears when you hover over a shape. The information about the comment is stored in the comment cell of the Miscellaneous section of the shape’s shapesheet.
Annotation was added in Visio 2003 and is not associated with any shape, but with the page it is on. The information about the annotation is stored in the page’s shapesheet in the new Annotation section. Choosing Show Shapesheet while an annotation is selected will open the page’s shapesheet.
In previous versions you assigned or changed the shapes comment by using the Comment command from the Insert Menu. With Visio 2003, this action will create an annotation. To create a ScreenTip in Visio 2003 you need to choose Shape ScreenTip… from the Insert menu or Edit Shape ScreenTip… to change it.
John… Visio MVP