This tongue-in-cheek advice refers to the fact that these builds aren't finished, and could be buggy. And they're right—Flash, printing, and most of the settings pages don't work. But for basic browsing, the builds are actually quite usable.
The browser's look has been toned down in both cases, but other than that, Chromium looks like it's moving forward healthily, and it performs like its Windows counterpart. That is to say, it's fast. OS X Download here, Linux here. [Chromium via PocketLint]