Regarding SVG, Olivier Galibert added caching, and now we're able to render them at high resolution without much slowdown(probably a hiccup at the start). This is in latest GIT, not 0.173.

And regarding MAME 0.173 released today. Here's a quick list of new handhelds added:
- Tiger Copy Cat (2 versions)
- Spelling B (1979 version)
- Konami Gradius
- Konami Lone Ranger
- Nu, pogodi! (not finished emulation of this yet)