The Internet Explorer version has feature X (like pagerank). Why don't you?
The Googlebar project is an independent organization, which means that although we try to copy some of the functions in IE, we start from scratch without any access to how Google does things, and some features, such as pagerank, appear to be proprietary; others, like the new popup blocker and form autofill, are already built into Mozilla and there is no need for us to implement them. But if there's a search feature in the IE toolbar that you would like to see in the Googlebar, we'd welcome any contributions of ideas or code. We currently have no plans to implement pagerank or the voting buttons due to their proprietary nature (ie, we'd get sued!!).