Publisher is a useful page layout program if your goal is to print the end result to an inkjet printer. Publisher uses a RGB color space (meaning that it likes to represent colors using the same approach as that of your display screen or web site). This creates no end of problems when trying to send a file to a commercial printer.
I'm not complaining because I spend my day charging good money to fix these problems. Maybe Microsoft will get more compatible with PostScript as time goes on but it is not very likely since Adobe and Microsoft are in a legal battle about how Microsoft handles Acrobat files in the new Vista OS. Again it is the user that loses by having to purchase and learn workaround applications just to get a simple job done on time...
But keep in mind that I'm happy with the status quo since I see no shortage of work for me during the next 3 to 5 years...