There are a few smart people who can’t stand to use Firefox on Mac because they’re so hyper-aware of the OS X user interface. ((As an 8-year Mac user who loves the OS X interface, but still prefers Firefox to Mac, I’ve always found this curious. I feel like I should be one of those people, but I adapt quickly to not having things like the Services menu. Shock, horror.)) Although it doesn’t surprise me that John Gruber is one of those people, it does surprise me how close he seems to switching.
Other than background windows looking like foreground windows, all of his issues are either extreme power-user features (AppleScript support), things that are easily arguable (clicking on the URL bar selecting the URL), or things that Firefox could quickly steal from Safari and should make everyone happy (submenus with additional history items in the History menu.) Considering how small his concerns are, I think it says a lot for the Mac work people at Mozilla like Josh Aas have been doing to get so close to being used by someone so Apple-centric.