I used Firefox for years and now I'm realizing that Google Chrome is more complete and easier right after the installation.
First of all you don't need to install Flash Player to start surfing seriously because it's already integrated in the browser and it's updated automatically, so you don't risk for its various bugs and leaks.
If before the extensions were a Firefox exclusive, now, if you want switch browser, you can find similar addons on Chrome too. Adblock Plus is even easier on Chrome because you can create a filter right clicking on the ads you want to hide.
Moreover the integrated functionalities are various. Chrome has a very simple print manager and includes a good PDF viewer, absent from Firefox: you can fill this "lack" only with third part softwares like Foxit Reader that with its plugin can show PDFs in the browser too.
To view video files and listen to audio files on Firefox I must install Quicktime with its plugin (as I said in this topic) while Chrome can play at least mp3 and mp4 files directly.
Chrome is easier ti use for developers too: in fact with Inspect Element you can browse between website resources while on Firefox you can view only the source of the page.
Chrome is also safer because has a sandboxed structure and automatic updates.