In recent years more file formats have become open source. One of the first commercial file formats to do this was from Macromedia with the Flash SWF format. They were smart though and didn't release anything relating to the actual development format .fla though which was a good way (at the time) from completely stopping Adobe from competing on a level with Flash, or smaller companies and freeware developers from creating products that could compete with Flash. Obviously that's all changed now because Adobe just took the other route in the end and bought out Macromedia and therefore got the code for the Flash format anyway.

I'm not sure how long it will take for new file formats such as docx to take off and become commonplace. The problem is that these files are most used in business, and it is common practice to send files to other people in a format that can be commonly read by anyone. This means that it has to be the most basic form of format that can be read by any version of Word since Word 97 as you would be surprised how many people and companies are still using a version so old, or even older.

Thinking back on it, I don't actually think I used the Word .doc format when I was editing a file on both an Amiga and PC. I'm sure I used the much more primative .rtf format and I'm sure it was because we had to sometimes use Macs!