Accessibility
I'm a big believer in accessibility. A well-designed webpage should be accessible to all users, regardless of their operating system, browser, or visual or hearing abilities.
In Australia, the Disability Discrimination Act requires that web-pages also meet accessibility requirements, however the actual legislation is rather toothless -- the Human Rights and Equal Opportunity commission have a set of guidelines which state conditions when a business may be exempt from accessibility requirements -- and there are quite a few. This, combined with the rarity of having accessibility disputes actually reaching court, means that Australia abounds with poorly accessible websites. Some are virtually unusable in anything but MSIE, with the Commonwealth Bank being a case in point.
Today I discovered that the iOrder. It requires a huge amount of browser-specific technology, and even displays a 'Your browser is not supported' screen to users of Mozilla and other browsers. It doesn't help that their phone service for ordering documents is currently down.
While I'm all for providing an enhanced experience for those people with appropriate technology, I don't believe that's a good reason to exclude everyone else. And when it comes to ordering paperwork from the tax office, being able to receive that paperwork is the primary enhancements that most users will desire.
