Microsoft has stepped up to the plate to retire Internet Explorer 6. Why is this important? Because many early web applications were developed specifically for this old browser, and programming things to be compatible with it and with current browsers is really hard. This browser refuses to dissapear, and current practices break it badly. Microsoft emphasizes that IE6 poses significant security risks and even companies using it for internal purposes should plan an upgrade path to IE8.
Take a look at the migration website: http://ie6countdown.com/
The statistics reveal the areas of the world still most dependent on IE6: China (34%), South Korea (25%) and India (12%) have some of the highest numbers. Why? A user base on older equipment, default installs, and highly customized non-English based applications lead my speculation.
With the move away from IE6, hopefully we will have better compatibility and support of the adopted standards for online browser protocols. Removing the requirement to write extra code for every browser that handles CSS differently makes life easier and more efficient for anyone writing code for online use. With the change, making websites work the same in every browser becomes easier. We hope anyway.