I upgraded my dev site to 3.2
I am using a child of twentyten with customization, menus, sidebars and widgets.
At first it seemed to display correctly.
I switched to 2011 to see what that theme was like, played around a bit. And went back to my custom child of 2010.
At that point I lost the display of the sidebar and footer widgets.
So....
Some issues I found that others may find helpful to know in advance:
After the upgrade, the sidebar & footer widgets holding custom menus weren't displaying. The menus were still there and I had to add the correct custom menu back to the proper sidebar widget. As I had several for many different page templates, this was a bit disconcerting.
I also had notes on what went with what, so no big deal.
But just a heads up to others who may run into the same thing.
On my other sites I haven't upgraded yet, but will take even more detailed notes on this.