The term "runway vacated" means the entire aircraft is clear of the runway surface. Taxiways crossing the runway do not count as vacated—you must exit the runway proper. Once you report this, ATC immediately releases the runway for the next arrival and switches you to ground control for taxi to parking.
ATC may also clear you to land and then instruct "continue taxiing, no delay," meaning you should not stop on the runway. This is common at busy aerodromes where the next arrival is very close behind you. You accelerate the aircraft to a safe taxi speed and turn off at the first available exit.