I have a user who uses Word as his e-mail editor. Often when replying to an e-mail, he'll insert his comments into the body of the original e-mail. Since he is using Word as the editor, these show as [User Name] Comment Text in a contrasting color. However, some users see the comments in their Outlook, and others do not. I've tried Selecting/DeSelecting Word as the e-mail editor on the recipients, and it does not seem to make a difference.
We are using Exchange 2007 with Outlook 2003 and Outlook 2007 clients along with a few Entourage Clients. There does not seem to be a pattern related to which client is used, but Entourage seems to be more likely to have the problem.