The author actually just gave a talk (actually finishing it) and he explained: he did not like the code style (svg.js does not use semicolons at the end of the lines).

Well that is what he said. But I believe having created Raphael.js in 2008, much before svg.js existed, also influenced his decision.

Same question. I was using Raphael.js earlier and had to switch to svg.js for SVG specific features, and it's quite a nice library, though perhaps not as developed as Raphael in terms of documentation.

The only possible conflicting goal I can imagine is that one of svg.js' goals is to be as small as possible (e.g. generating an <ellipse> instead of a <circle> to increase code reuse between the circle and ellipse shapes[1]).

[1]: http://documentup.com/wout/svg.js#elements/circle

I've found svg.js unusable for any project I've had as it requires all svg content to be created with svg.js and no imports.