I thought the situation was a little like Android. Google develops an open source version (along with as many independent developers who wish to contribute), then sticks on a bunch of proprietary BS and sells that version to phone companies. If chromium is to chrome like vanilla android is to android with g-services, then I guess my question really becomes: is google making this change in the underlying code base, or just in the BS they put on top?
Or am I confused about how the connection works between chrome and chromium?