The main reason for switching to Firefox is that, overall, it's better than Chrome. But there are other reasons. The most important is that Firefox is the only major browser that is written to serve users and the open web. Other leading browsers may sometimes do that, but their primary function is to serve the needs of giant corporations -- Apple, Google and Microsoft -- none of which has any interest in preserving your privacy. Usually the reverse, in fact.
It's also worth mentioning that Firefox is the only leading browser that is genuinely open source. Apple's Safari may be based on open source, but only because forking an open source development offered Apple a relatively quick and easy entry into the browser market. Google's Chromium is open source, but Chrome isn't: it comes with hidden extras.
Mozilla's commitments to your privacy and to the open web are much more important than what any of its staff might have done in the past. In any case, Mozilla co-founder and former chief executive Brendan Eich has already quit, and Mozilla chairman Mitchell Baker has very publicly apologised. At this point, anybody who still thinks boycotting Firefox is a good idea is behind the times. It needs -- and deserves -- your support.
Businesses, of course, tend to judge things on merit, which is where the argument for Firefox is strongest.
I switched back to Mozilla Firefox in the middle of last summer, when it first became a better browser than Chrome, at least for me. Chrome was crashing too often, and in particular, Chrome's built-in Flash was crashing multiple times per day. When it was working, Chrome often failed to display web pages: where the text and images should have been were pale blue blank screens.
I put this down to Chrome's heavy consumption of memory and other resources. (Yes, it's my fault for opening too many tabs, but that's how many people work.) In March 2013,, a small utility that would close all the tabs and recover memory. But while that was a temporary answer, it was the wrong answer. Firefox supports 80 or more tabs on the same PC. What's more, Firefox keeps the tabs the same size, so I can still read them.
Also, after Firefox crashes, it doesn't try to load all the old tabs at once, so you don't have to wait for it to catch up. Firefox only reloads tabs when you click on them.
Perhaps surprisingly, Firefox is now roughly as fast as Chrome, and sometimes loads pages a lot faster. It used to be slow, but Tom's Hardware published a test last June (Chrome 27, Firefox 22, IE10, And Opera Next, Benchmarked) which said: "Firefox 22 pulls off an upset, replacing the long-time performance champion Google Chrome as the new speed king!" There's not a lot in it. However, if you switched to Chrome for its speed, that may no longer apply.
While using Firefox, I've discovered many other ways in which it's better than Chrome. In particular, it's much easier to find the tab you need. First, tabs always stay big enough to read, and you can set a minimum size. Second, there are arrow keys you can click to scroll through open tabs. Third, if you hold the mouse pointer over the tabs, you can use the mouse-wheel to whiz through them really quickly. Fourth, one click provides a drop-down menu of all your tabs. Fifth, you can organise tabs into groups and save or reload groups of tabs: this is very handy if you switch between several tasks. Sixth, you can have Tree Style Tabs that work like a folder tree in Windows Explorer. Indeed, you can even have tabs tiled if you want, using Tile Tabs 11.5.
Another way to find a tab is to start typing the address in the address bar: you'll be offered the option to "Switch to tab".
Firefox is also better at using multiple search engines. You can still search from the address bar (Awesome Bar), as with Chrome, but Firefox also has a separate search box. This makes it easier to use different search providers, by picking them from the dropdown list. You can also add website-specific search engines. Amazon, eBay, Twitter and Wikipedia are defaults, but you can add many more: there are thousands. However, the default Google makes the search box a handy calculator.
Firefox has other usability benefits, and those are being enhanced in the latest 29.0 (Australis) beta. This is faster, has a new Firefox Sync system, and has a Customize menu that makes it simpler to configure Firefox how you like it. Yes, it does look more like Chrome (below). The release version is expected later this month, which could be a good time to make the switch.
The case against
Chrome does have two significant advantages. First, it uses separate processes for different website, and second, it is sandboxed for extra security. If a website creates a major problem in Chrome, it will only take one tab down not the whole browser. Unfortunately, this is also the main reason why Chrome is such a resource hog. Whether this is worth it probably depends on which websites, plug-ins and extensions you use, and how often tabs crash. I don't have a problem with bad tabs, so I prefer Firefox's ability to support more tabs without slowing down. Your experience may be different.
Security is the area where Firefox is weakest, as shown by its failure to survive attacks at Pwn2Own conferences. However,, so using Chrome doesn't guarantee security either. Again, it depends on the types of websites you use and whether your work is valuable enough to attract hackers. If so, you could either run key programs inside a separate sandbox, such as Sandboxie, or use a virtual PC. Either way, you have bigger threats to worry about than Firefox.
Every program has its pros and cons, but the balance between Chrome and Firefox has tipped over the past year. Firefox has always respected your privacy, and now, all things considered, it's also winning on merit.