Why SMIL?

1. Like HTML and SVG -- a declarative markup that leaves details up to the viewing software
2. For designers and programmers
3. interoperable with JavaScript
4. runs on many mobile devices that don't have scripting engines
5. Describe what is to be done:  change this object along this path, varying its size and color as it moves.
6. No need to guess dt such that dx and dy can be updated smootly on client's screen
7. No need to centralize large setTimeout loops for animations
8. No worry about cross module variable contamination
9. Less development time (10 x less for authors).
10. Examples galore.
11. maintainability of code (12 lines is easier to maintain than 120 lines)
12. same sort of syntax as other SVG modifiers: filters, gradients, clip-paths, masks, patterns, replicates
13. modularity (animations are all separable)
14. behavior resides with the thing that is behaving (improved semantics and accessibility)