I'm sure you'll be surprised to see me posting the following . . .
A guide on how to install IE7 Beta 2 Preview Release alongside IE6:

Download the installer file from Microsoft, but
don't actually run the installer.

Create a folder labelled
7 inside your Program Files\Internet Explorer folder.

Open the installer with WinRAR and extract the contents into the
7 folder.

Open Notepad, and create a
blank text file. Don't write
anything in it.

Save the file as "iexplore.exe.local" in the
7 folder.

Run the new "iexplore.exe" file in the
7 folder.
You now have a standalone/local IE7 Beta installed alongside your pre-installed IE6.
(Or better still ... stuff IE7, and use
SeaMonkey instead!)
I have to agree about the GUI in IE7. What the blinking flip have they done by arranging the toolbars like that?!?
If anything, on the basis of that total train wreck of a GUI alone, IE7 is not going to win many fans (if any) and
it'll probably have even more people moving to Firefox and Opera. Of course, IE7 is only a beta product at the
moment, so I wouldn't 100% rule out a "Classic" UI option being added before the browser is finalized.