interesting argument, and it's definitely worth thinking about these kinds of UI assumptions. But I'm still in favour of keeping them. First of all even if th

interesting argument, and it's definitely worth thinking about these kinds of UI assumptions. But I'm still in favour of keeping them. First of all even if they are 'training wheels', the user interface should be understandable by someone who's never used a computer before. Buttons and sliders have real-world analogies and as such if correctly implemented are easy to understand without requiring that the user has prior knowledge of 'the web2.0 way of doing things'. Secondly, sometimes I just want to zoom right out, or zoom right in, without having to pass through every step in between. This is something that sliders afford which continuous scroll-to-zoom or click-to-zoom doesn't. Thirdly, right-click to zoom out is not very webby at all, and I doubt many users are comfortable with that UI pattern. I've certainly never used it. Keeping 'webby' is hugely important - and not in conflict with my first point - because there are two relevant points to be aware of when implementing a UI: Firstly you're teaching users how to use the web, and secondly when you implement a UI you can expect (but not require) users to use it in the same way they use other web apps. Right-clicking fails badly on both of these.