I hate that phrase, truly, madly, deeply hate it. It's only ever used by TV presenters. They must stop and stop now.
"And don't forget to add that all-important pepper to your casserole!"
"And don't forget to get that all-important local authority search!"
"And don't forget that those all-important things that are said to be all-important aren't even really important at all, most of the time, never mind all-important!"