Google Change -- Why? The usual answer
It works for the people who are designing the application. I guess eventually it, like many Microsoft products, will require Dummies books, O'Reilly books, Sam's books, etc. to explain just what is going on.
White space? End users do have the option for the more personalized (and cluttered) iGoogle home page. I don't know that IE has that option as the user is directed to some Microsoft page chock full of stuff upon launching IE.
I have to agree with Ron_007 in that the corporate people offering all these hot options on just about every Browser need to remember the needs and wants of their customers. We ain't all 23 and bored with the same old thing!