The latest dev channel release, www-client/chromium-7.0.503.1, builds with use_system_icu=1, which means one less bundled library. It also seems that the binary size of /usr/lib/chromium-browser/chrome is now smaller.
We have still quite a lot of bundled libraries though, but we're really close to building with system sqlite. I'm working on upstream patches (both Chromium and SQLite) to make this possible.
Please note that as www-client/chromium uses more and more system libraries, it will also require more testing on the Gentoo side, because upstream QA only tests the bundled configuration.