Saga are saying that the number of properties worth more than the nil-rate band has gone up.

Yes, but married couples get two nil-rate bands. And next year there will be an additional allowance for property.

Inheritance Tax is currently only an issue for a couple with over £650,000 of assets. And an individual who is not part of a couple, with "only" £325,000 to leave, will still be able to benefit from up to £175,000 for their property as well in due course.