Looks like a good replacement for the vector side of flash and is partnered with Adobe. The SVG looks very clean and it is nice to have it load SVG files and create on the fly. Also awesome that it is made by the developer of the Raphael library.
One problem with intensely declarative content is bad naming, verboseness and strange groupings/ordering. Silverlight had this problem and SVG has it a bit in terms of content from other programs like Illustrator, SVG exporters etc. Adobe will probably be developing tools to edit this maybe? SVG support is still a little lagging and the web is missing vector frameworks since Flash has been sidelined with mobile.
There's a great little node.js-based tool called SVGO for removing the fluff and optimising SVG files: https://github.com/svg/svgo