That's the determination of western intelligence agencies according to this piece in the Washington Times:
Earlier this month, several Arab and Hebrew newspapers reported that Mr. Mubarak recently sought treatment for his ailment at a hospital in France. A senior Egyptian government official interviewed for this article said those reports were "without any factual basis whatsoever."
There are, however, other indications that Mr. Mubarak's health is failing. In March, the Egyptian leader traveled to Germany for what at the time was said to be gallbladder surgery, a treatment that took him out of action for six weeks, according to a special report on Egypt in the current issue of the Economist.
An intelligence officer from a Central European service told The Washington Times last week that his service estimates that the Egyptian president will be dead within a year, and before Cairo's scheduled presidential elections in September 2011.
Both the National Intelligence Council and the U.S. Central Command have tasked intelligence analysts to start gaming out scenarios after Mr. Mubarak's death and how his passing will affect the transition of power, according to three U.S. officials.
The best outcome of such a scenario for the US would not necessarily be the best for the Egyptian people; Mubarak's son succeeding him:
While Mr. Mubarak has declined to endorse a successor, the new law on presidential succession provides a major advantage to Mr. Mubarak's son, Gamal Mubarak, 47. The younger Mr. Mubarak is head of the powerful policy committee of the ruling National Democratic Party (NDP), the party that has led Egypt's government for more than 50 years.
Other potential military rivals to Gamal Mubarak, whose nickname is "Jimmy" in U.S. policymaking circles and among the Egyptian elite such as Mr. Suleiman, are not formal members of the NDP.
If Mubarak were to die before next year's presidential elections, whoever emerged as leader in the immediate aftermath would have a tremendous advantage. Mubarak has used the power of the state to rig elections in the past and there is no reason to believe his successor will do anything different.
Mubarak's death is apparently not imminent and he may hold on for another 12-18 months. But when he passes, there will be a danger of chaos in America's most powerful Muslim ally in the Middle East - something we can ill afford given the challenges in Iraq, Iran, and elsewhere.