It wouldn't have been a problem if they had done so the way that WebKit, Opera and Mozilla developers have done so. By prefixing it clearly lays out that it is

It wouldn't have been a problem if they had done so the way that WebKit, Opera and Mozilla developers have done so. By prefixing it clearly lays out that it is a "vendor" specific property implementation. That implementation can be discussed, modified or accepted and become a standard non-prefix property. It's happened a few times where the WebKit implementation has had to be reversed to match another vendor's approach. This is good. It has gotten us closer to using CSS3 in a shorter period of time than we have with any W3C standard. The way that both Microsoft and Netscape did it in the 1990s was not only the wrong way to do it, it was a malicious approach aimed at segmenting the web. And Microsoft's biggest sin was that they froze IE at version 6 for over 5 years, ensuring that their mishmash of standards and proprietary implementations would weigh on the Internet.