What is the difference between Word ML in 2003 and 2007?

Hi

Here is a bit of confusion, in Microsoft Word 2003, the application is still using the doc file format to store the documents, but it can also use the xml file format to store the entire document formatted as WordML.

WordML is a very nice language, and I already started using it in our reporting, ASPX page generating a dynamic word document, here is a sample:

http://livetechnologies.ca/Lists/Blog/DispForm.aspx ID=30&Source=http%3A%2F%2Flivetechnologies%2Eca%2Fdefault%2Easpx

Now after having a look at Word 2007, everyone there is talking about the new Word File Format, and how can you save everything in WordML.

But Word ML already exists today :-)

It is a bit confusing, is the new word document format is also the old document format enhanced, or a new redesign for the Word ML language

Thank you