I write a web application for corporate environments and browser compatibility is sometimes a bitch. With over half the browsers in corporate networks still using IE6 I am forced to develop code that works on IE6, IE7 , IE8, FF, Safari. I have found that the other major browsers like opera, chrome and konqueror just plain work. IE6 (and to a lesser degree IE7) is holding back the internet and tieing developers hands with insane CSS or javascript hacks.
I know everyone loves to slam IE but despite being slow IE8 has good enough standards support that it doesn't need hacks any more to work.
The problem with the current browser wars is that their are so many combinations. If it takes QA an hour to test a change once - it will take them an entire day to test it on the top 8 browsers. If we could mandate the client platform FF would be a great choice but whoever these vendors that only support IE6 are need to get off their asses because its giving me a headache every day.