When you are working on a new website, what combinations of browsers and operating systems do you target, and at what priorities? Do you find targeting a few specific combinations (and ignoring the rest) better than trying to strive to make them all work as intended?
Common browsers:
Common operating systems:
I'm doing:
Where I work, we target
We are not specifically targeting any Linux browsers, but if they work in the list above, there's a good chance they work everywhere. We are also testing against Google's Chrome browser on Windows now.
It depends on your audience. If you are heavy on tech users, you may have 50% of you users as Firefox. If you have lots of mom and dads, you will probably have 75-80% of your users being IE 6 or 7. You probably need to get a alhpa/beta out with Google analytics so you can get a measure of your audience.
Mainly I just target browsers as the sites I've built don't really depend on anything OS specific. As mentioned above, YAHOO's graded browser support guide is a good starting point on determining which browsers yous should/could support. And Yahoo's User Interface library (CSS+JavaScript) helps massively in achieving this.
But when developing sites I primarily do it on Firefox2 as it has the best web developing tools (firebug + wed developer toolkit). Then I also test my sites with Opera 9.5 as it's my browser of choice for browsing. I've previously lost all hope on supporting IE6 at any reasonable level so these days I just inform my users to upgrade to IE7 which is almost capable of displaying sites similarly to FF2/3+Chrome+Opera.
FF3 and Chrome are so new at the moment that I tend to ignore them, but I must say: They're friggin fast! My javascript/css heavy sites are noticeably faster with them.
Where I work, we test the following (in this order of priority, based on data from google analytics), all on Windows:
We don't bother with Opera or older versions of browsers since the percentage of users is very small, however we do our best to code everything to standards, so there shouldn't be any big issues.
Of course, like Milhous said, it depends on your particular audience. YMMV.
The standard suite I'm used to is:
You could also generically claim support for IE6/7, Gecko, and WebKit... and it covers everything listed here but Opera, plus a few not listed. It's just a lot harder to test just the rendering engine and not the specific differences in browser versions and feel comfortable with the results.
I agree you should try and make it work in all, but if it is a new site I would seriously consider dropping support for IE6. From a development perspective it will save you hours of hair pulling if you don't need to support it.
You'll have to weigh this against your intended audience and whether you are willing to lose some customers that won't be willing (or able) to upgrade their browser.