- New Add-Ons Manager: gives you more space to manage your Add-Ons, Themes and Plugins. Customizing your browser has never been easier!
- HD Video: Watch hardware-accelerated, super-smooth, HD-quality HTML5 video on YouTube using the new WebM format.
- Privacy improvements: Mozilla always puts privacy first, and this latest beta fixes flaws in some Web standards that could expose your browser history.
- Crash Protection: Experience uninterrupted browsing (now available on all platforms) - when a plugin crashes or freezes, you can resume browsing by simply refreshing the page.
- Performance: We know that performance is important. In this version, we focused on improving responsiveness at start-up and during page loads. This is just the beginning for performance improvements in Firefox 4.
However, for some cosmetic changes tabs are (so far) going to be on top of the window, copying chrome, and the bookmarks bar is going to be discarded for a button with dropdown. Now I am really against this move, however, note that this is the beta and just like apple's safari beta (with the tabs on top) there probably will be changes. I bring my viewpoint from the viewpoint of efficiency.
Also, regarding the pixels and the argument that tabs on top take up less space, even looking from chrome for mac that space is minimal, and I for one prefer tabs on bottom. I hope that there will be an option for this. As for the lack of a bookmarks bar, I am very disappointed. A bookmarks bar (in my opinion) is far more useful than a dropdown. And plus, for a bookmarks bar you can hide it (I'm not sure whether you can get back the bookmarks bar as I haven't tried out the beta) so if you want to save space you can do that. Having to click the button then click the site is even slower than making keywords for the site (Ex: a for apple.com) and pressing enter. It is far less efficient in regards to mouse clicks when you look at the bookmarks bar, where one click gets you to the site that you want to go.
I'm just going to include a quick screenshot (also shown in appleinsider/macrumors) however for some reason the tabs are not on top.
However, I am for crash protection (plus I want to see tab isolation in future builds of firefox). I am also for increased performance as well as memory usage. Yesterday, I had an instance of firefox open and I closed 71 tabs, and the memory usage did not drop at all (It stayed at 738 MB). Now that is a more extreme example, but I hope that in firefox 4 memory usage can go down if I leave firefox open for prolonged periods of time.
Well just a short rant on firefox 4. I might try out the beta in the near future just to see how it goes, though looking from the forums perhaps I should wait as there are still numerous bugs (it is a first beta, after all).
Here's a screenshot to prove my firefox usage :P This is another instance, but somehow firefox got up to almost 1 GB of memory...