Good that you mention this point. This is for me the main reason to use jQuery in a project: backwards compatibility. I am gladly in the position where I make my own business decisions and so I choose which browsers I want to support. That said I totally refuse to support super-old browsers like IE6. I even refuse to support IE9. If someone has trouble using a site built on modern standards: Go get a modern browser. If it looks shitty on your old IE6 then don't blame me.