Chrome, not Gold or Platinum.
Sure, the new Google Chrome browser is fast and lean, but it didn’t hit a home run. The main browser for me is still Opera. (Geert, please update to Opera 9.52, because your 9.02 version is reaaaaallly old).
Security-wise it might also be at the top, but Opera ain’t no slouch either. And small extra features like Inspect Element look cool.
But, here are the things that will keep me from using Chrome as the main browser (as well as any other, actually):
No integrated mail.
No mouse gestures or click+roll enhancement.
No handy toolbars with things like Find on page, Find Next, Fit to Width, Zoom percentage dropdown menu.
Handling of tabs still easier in Opera (Shift+Click to close, Duplicate opens new tab, not new windows like Chrome).
Browsing logic. In paged documents, pressing space repeatedly will drop you down until the end END after another space, you will move to the next page. No other browser will do this.
Blocking content per site.