Firefox's recent changes have impressed me

I am impressed by recent changes and changes in progress to Firefox, namely:

• an optional PDF viewer written in Javascript;
• a new Downloads dialog box, with a matching Navigation bar button to show/hide the dialog. I definitely prefer this to having an entirely separate window opened (available only in the Nightly build at the moment);
• an option to open links in a Private Window. This is an improvement over the previous option, which was to switch the entire browser into Private Browsing mode (OK - I may have the name of that feature wrong) (available only in the Nightly build at the moment).

Yay Mozilla!

Note: I am well aware that these features have been available in Chrome for some time. I give Google credit for the excellent browser that is Chrome but my preference is for Firefox.