I'm not a fan of Mission Control at all... i prefer the Snow Leopard way; I find it easier / faster to switch apps than having the Spaces across the top.
When I have multiple applications open in different Spaces, if the app I want to switch to is on a different Space, I have to double-click on it to switch to it. If it's on the same Space, then I can single click to switch... seems like it 'deactivates' the current window I was on then switches / activates the app I'm switching to on the second click.
This is just an annoyance.. anyone seeing this, as well?