To select a windows from window picker you must now click or press enter rather than just release the keyboard shortcut

Thanks for reporting this bug and help to make ubuntu better.
I'm not very familiar with the shortcuts in that area and don't think I've specifically changed that. Can you please clarify and report the steps to get to that point?

Thanks a lot.

I've got here by searching "windows picker 10.04 different".
With the new OS version is changed the way it works.

I've compiz and compizconfig-settings-manager, I've personalized "window picker" plugin (it's in Window Manager section, the bottom one) to get it start by pressing Super+Q (where Super is the windows-logo key) and few other thing (like the times it takes etc...)
Now I'll describe the way it works.

Until 9.10:
By pressing Super+Q Window Picker start and stays up as long as I press the Super key (it doesn't matter if I release Q); then moving the pointer (WHITOUT clicking) on the opened windows/applications will change the highlighted one, which is the the window/application to be selected when I'll quit Window Picker (that is when I release the Super key).

In 10.04:
By pressing Super+Q Window Picker start and ALWAYS stays up, until i press again the combination Super+Q; and this time moving the pointer (WHITOUT clicking) on the opened windows/applications will STILL change the highlighted one, BUT this time it won't be the window/application to be selected when I'll quit Window Picker.
With 10.04 I have to click on the desidered window/application to get it selected, the highlighting doesn't influence anything.

Sorry if I've done any mistakes and the word written in strong case aren't intented as shouts but as highlights, because I've done the two descriptions by using copy&paste, resulting in some possible confusing similarities.

Hum ok, compiz can have a lot of issues with clutter, hence the fact that this different behavior wasn't caught.

Could be good to revert to previous behavior on maverick.