For the last few weeks I have been using the chromium browser as the main browser both at work and at home. There's an Ubuntu PPA containing .debs of nightly chromium builds which works fine on Debian sid AMD 64 (as others have mentioned).
The "killer feature" for me about Google Chrome when it was first announced was the tab/window process isolation. What I really like about chromium is how fast it feels. Opening new windows is blazingly fast. I can reorganise windows and tabs however I like (which I used to enjoy doing in Epiphany before the feature disappeared).
I installed chromium without high expectations. I suspect the features I like about it (speed, stability) will end up in other browsers and I've been expecting to move back to Epiphany (or perhaps even Firefox). However, maybe I'll just stick with chromium for a while.