I am now using Google Chrome on all the three platforms it is available on.
I have been using it on Windows since the first day it was made available.
And now that official test versions are available on both Mac and Linux, I am using them as well.
It replaces the test builds of Chromium for me on the Mac. This is good considering I had to manually download and replace the previous build of Chromium on the Mac. The official build comes with an auto-update mechanism similar to the Chrome on Windows.
Google Chrome is also running decently on my Ubuntu installation. Of course, there is no support for Adobe Flash. Other than that it has been rather awesome. Google installed its own repository in Ubuntu for auto-updates. However, the one it added did not work for me. So I had to manually add another one.
Now, Ubuntu software updates include the latest version of Chrome. So that is pretty awesome as well.
I hope Google gets the open source edition of Chrome which is Chromium included in the official repositories of popular Linux distributions. This would give a solid alternative to Firefox to all Linux users.