Interesting. I'm wondering what those sources of income are? I'd assumed that the royals mostly got their money from the Civil List via Parliament.
They are, basically, talking about the Civil List. It was restructured a few years ago to be more closely linked to how much money is garnered from the Crown Estate by the Treasury, and that meant a big jump because the Crown Estate is currently generating money at an impressive rate - but if the profits of the Crown Estate declines, it will reduce accordingly.
Besides that, the Queen receives revenue profits from the Duchy of Lancaster - these are generally used to pay the expenses of the other members of the Royal Family (only the Queen and the Duke of Edinburgh receive civil list payments, and the Prince of Wales (entitled to the revenues of the Duchy of Cornwall) is the only other member of the family to get money from being royal - the Queen has to pay for everybody else and the Duchy of Lancaster revenues have generally been used for this).
I seriously doubt thats her personal worth. Its prolly just the money she gets from the govt to run the monarchy.