I think I had a quick firefox 4 post in the past, but from then I was already a skeptic. I tried the firefox 4 beta for a short while and I really didn't like the interface, where everything just seemed to take up so much room. It just didn't seem like an improvement from firefox 3, but today I thought, why not try the new firefox 4? If I don't like it I can always switch back. I checked for compatibility for all my addons and all I needed to do was update my 1password to the latest version, and I downloaded firefox 4. I am was not really an early adopter of firefox 4 as I was pessimistic about its performance. However, as I started to use the browser I quickly changed my viewpoint.
Just to start off this is how I set up my firefox 4, and it's fairly similar to the setup to my firefox 3.6 layout, just that the interface has changed slightly.
I filled over part of the toolbar, it just includes a number of bookmarks and my bookmarks folder. There was a built in button for bookmarks but I thought that it was too general, as it showed all of the categories just like the bookmarks manager. I would rather have a folder favicon with the name "bookmarks." If you are that curious I assure you that these bookmarks aren't to any "naughty" sites. SO you might say, "Hey, this looks so similar to safari," which is true. It appears that firefox now has many similarities to safari (a la reload button on the right of the "awesome bar," opera/chrome, due to the tab placement. By the way, the tabs were originally on the top, but it was fairly easy to bring them down (all you do is right click on the tab bar and deselect "tabs on top"). I find that I'm not a very big fan of the new square block icons firefox 4 utilizes, I would prefer the old icon set (so now borders, just have the icon as is), though not that big of a deal.
In firefox 3 I had the original huge back button but when I used 4 I just saw it as too bulky and used up too much space, so I rather had the smaller buttons, which look identical to those in safari. The two icons next to the URL bar are for noscript, one to temporarily allow all scripts on page and the other to selective activate or deactive scripts temporarily or permanently. Then there are the bookmarks I talked about earlier, and lastly there's the icon for my webmail checker. I found it interesting that they took out the spinning circle, that indicated a site was loading. Rather, the have a new spinning circle as part of the space normally taken up by the favicon in the actual tab. I actually prefer this.
Since it's firefox I'll just mention addons, here's a screenshot of my addons, nothing special. I also disabled a number of plugins. Some people have been complaining that the addons page is now in a tab (like chrome) but I personally don't mind. I've been having troubles previously in greasemonkey where when I go to the extensions manager I would see a huge icon for greasemonkey scripts, messing up the height of the tabs in the extension manager. Having the addons in a separate tab fixes this. One thing that I don't like about this new format is that I have to click on the cog at the top to change settings, which I found to be annoying.
I will delve into some of the technical aspects of firefox 4 on mac, one thing is that it's a 64 bit browser, with plugin isolation (but not tab isolation). It uses far more memory now (in fact, right now it is using about 650 MB of RAM, which makes me wish I had more memory in the first place- I have 2 GB). Here's a screenshot of the isolation process shown in activity monitor. I have read reviews of firefox 4, but I didn't pay attention too much to the isolation processes that firefox uses, so I won't be able to give a detailed description of how this works. The firefox plugin process is highlighted. I personally like the feel of a 64 bit browser (which is more important now that it uses so much more RAM), though at times I get messages telling me that a plugin doesn't work in 64 bit mode and requires a restart to 32 bit mode. I'm not sure whether this will be a huge problem over time, but for me it was when I was using hotmail so I just disregarded the message (I really don't like the silverlight plugin in hotmail).
One of the more touted new features in firefox 4 (other than speed and performance upgrades) was a project originally known as "tab candy," which is a new way of tab management. An example of it is shown below. The shortcut for it (at least on the mac) is command-shift-E, and then you see this window.
Some other reviewers have said that it's clunky and hard to use, but I personally like it, since I always have many, many tabs open (especially when I look for research articles). It allows me to sort through the tabs easier, though I can see how this process could be more streamlined and efficient. So basically once in the window you can rearrange tabs, make new tab groups. When a tab group is selected the other groups aren't seen. So for example if one group just has hotmail and gmail, while the other groups have yahoo and bing open and I select the first group, I will only see the tabs for hotmail and gmail, and not the tabs for yahoo and bing. I like this as I always have many windows open. By default I think every window is its own tab group. One flaw that I saw with this new system, is that when I'm in the tab management mode and I click on a tab the animation isn't exactly smooth, so I'll see block text until LI reach the actual page. Hopefully they'll fix this in the next release
In conclusion, even though firefox uses much more memory I think it's worth it, since I gain speed and many new features. I would highly recommend this browser for those who are using firefox 3 and internet explorer, and I assume that those who use chrome and opera are diehards anyway so (jk). Over time as I use firefox 4 more maybe I might add more to this, or create a new entry altogether.
Edit: Some additional thoughts, I miss having a reload button (there is one, but I wish there was a real icon for reload next to back/forward buttons, but I looked through the icons and it was not there). To those saying "just press control-R" I just want the choice, seeing it's not that hard to add a reload button. Also, flash seems to crash more often than before. Regarding the silverlight problem, I downloaded and installed the newest version of silverlight and I haven't had any problems it (I'm having more problems with flash now, in fact...).