Got the prompt and updated last night, kinda liking it overall. Some observations:
- Not cool that I selected Customize instead of Express (where I disabled everything) and Windows promptly ignored them.
- WiFi is kind of spotty on my intel 6300 card, not even the newer driver on intel's site seems to help much (although it did improve noticeably).
- Tiles for non-metro apps seem to be stuck to selected color only, there is no option to show a color more akin to the icon (probably one of the few that actually liked that)
- Got so used to press Win+C to check the clock, annoying that it's no there now

Is there any live tile that shows the time?
- Not having a keyboard shortcut for moving apps through desktops is an inconvenience.
- For some reason Win+Space to change keyboard distributions stopped working for me (it was working fine yesterday post update).
EDIT:
- VS2013 for some reason is constantly automatically switching back to a specific tab I have open. It's hilariously annoying.
Not the same though.
I can get used to the new start menu just fine, but the lack of full screen, sort-able, all apps is kinda annoying
http://neogaf.com/forum/showpost.php?p=173591661&postcount=154
Link at the bottom. The post also demonstrates the drawback of doing this. You're not going to get separate colors for focused vs unfocused windows, and you will likely end up with a weird gray box in the unfocused window.
I did it and it's kinda better, but the gray box sucks and some desktop apps seem to think I actually have the classic style in use :/