This matter has been discussed many times.
The phrase "cleared for the ILS" was interpreted by some pilots to descend well below the glidepath before interecepting the LOC - I've seen aircraft approaching Heathrow go down to 1200ft over Central London so Heaven only knows what used to happen before we had altitude readout on SSR. So, the UK introduced a procedure where aircraft were cleared to intercept the localiser maintaining the last assigned altitude and then told to descend on the ILS if it was clear to do so. Reason being that there is a lot of GA traffic and helicopters flying at up to 1500ft right under the Heathrow approaches and it was necessary to provide safe separation. Same applies at many other airports too.
Keeping vertical separation against traffic turning "inside" usually only applies when two runways are in use for landing. If they are both going for the same runway, horizontal separation is usually provided.
rubik101 said: "I would advocate continuing the approach and descending if you have no instructions to the contrary" Well I DEFINITELY WOULD NOT, unless it was comms failure. You have no idea what might be underneath and on countless occasions it is necessary for aircraft to be told to maintain an altitude whilst on the localiser. Police helicopters, ambulance flights and other priority movements may be right underneath and if you gaily descend without a proper clearance you are taking a risk.
HTH.