The ever expanding universe of Microsoft Office workers may be heading towards utter chaos as organizations migrate to Microsoft Office 2007 programs sometime next year - the reason being the new and efficient but equally confusing Office 2007 file formats.

With Microsoft Office 2007, Microsoft has introduced at least 20 new file extensions and some of the extension names are not very obvious. For instance, when you see a file attachment like check_this_slide.sldx in your email message, you might confuse it for a virus or an unsafe extension though it's just another PowerPoint 2007 slide file.

Microsoft Office 2007 File Formats
Here's a complete list of new file types that have been introduced with the most common Office 2007 Programs - Word, PowerPoint and Excel. This list has 20 entries and we haven't touched Visio, Publisher or Microsoft Access 2007.

Microsoft Word 2007 [4 New File Extensions]
• docx - Microsoft Office Word 2007 document
• docm - Microsoft Office Word 2007 macro-enabled document
• .dotx - Microsoft Office Word 2007 template
• dotm - Microsoft Office Word 2007 macro-enabled template

Microsoft PowerPoint 2007 [10 New Extensions]
• pptx - Microsoft Office PowerPoint 2007 presentation
• pptm - Microsoft Office PowerPoint 2007 macro-enabled presentation
• potx - Microsoft Office PowerPoint 2007 template
• potm - Microsoft Office PowerPoint 2007 macro-enabled template
• ppsx - Microsoft Office PowerPoint 2007 show
• ppsm - Microsoft Office PowerPoint 2007 macro-enabled show
• ppam - Microsoft Office PowerPoint 2007 macro-enabled add-in
• sldx - Microsoft Office PowerPoint 2007 Slide
• sldm - Microsoft Office PowerPoint 2007 Macro-enabled slide
• thmx - Microsoft Office Powerpoint 2007 theme

Microsoft Excel 2007 [6 New Extensions]
• xlsb - Microsoft Office Excel 2007 Non XML Binary workbook
• xlsx - Microsoft Office Excel 2007 workbook
• xlsm - Microsoft Office Excel 2007 macro-enabled workbook
• xltx - Microsoft Office Excel 2007 template
• xltm - Microsoft Office Excel 2007 macro-enabled template
• xlam - Microsoft Office Excel 2007 add-in

Microsoft says that these new Office 2007 XML Formats result in smaller file sizes and the increase the chances of recovering data from corrupted documents. There's no argument against that but still, the existence of "so many" file formats in Office 2007 is bound to confuse even the smartest Office geeks, leave apart the lady at the reception desk.

It's more like approaching the y2k day - you never know what would happen until the D-day when people actually migrate to Office 2007. Even Anti virus companies and Firewall vendors will have to release new patches soon to make sure their programs don't block or quarantine Office 2007 files due to "unknown file extensions".

The good point is that Microsoft 2007 Office program still allow you to save files in the older Office binary formats like doc, ppt or xls. And they are providing free compatibility packs to open Office 2007 docs with Office 2003/XP/2000 and vice-versa.