It would be nice if I could test IE9 on my home machine -- alas, ' tis still XP Pro until Santa (or my fairy godmother) comes through with some expendable cash.

We've a lot of machines at my workplace running XP Pro, Vista and Win 7. But without being able to compare the different browsers on my own machine (the workplace machines all suck badly) I'll just have to take anecdotal evidence of IE9 being better than IE8.
I've heard that Chrome opens a new process for each tab, so that probably explains the resource appetite you mentioned.
This entire afternoon has been spent jumping back and forth between Chrome, IE8 and Firefox to see just how much difference there might be (or not) between certain pages on each browser and the differences are so small as to be nonexistent.
The speed of Chrome is the only thing which has really jumped out and hit me.
As to your advisement about privacy concerns in Chrome (phoning home, etc.) I'll try to restrict my visits to porn sites unless using the other two browsers.

Just kidding. Actually, the Web pages I visit would probably bore them to death if they bothered to do a detailed look at my habits.