SVG didn't gain the needed momentum as it's approach was more revolutionary instead of evolutionary. Also Internet Explorer, although I'm not sure how it fits in this situation as it surely can't support all that fancy CSS required to do advanced graphics either.
Also, SVG can be embedded directly in HTML5 now. Also, Firefox 4 seems to be making progress on actually supporting SVG animations now.
I don't think SVG is dead, I think it's getting closer and closer to the point where people will actually be able to start using it as was intended. Not quite there yet though.
