This is better then Mubarak remaining a figurehead - that wouldn't have satisfied the people. The unrest would have continued with risks of it spinning out of control. The military has controlled Egypt for decades - Mubarak was military. This is just one military leader retiring and passing on leadership to his successor. This is a good outcome for the US - they appeared to support the people and democracy but get what they really want instead.
Shaffir to Herzog: Opposition failed to show leadership in political battles against PM (Haaretz)
from the article: Egypt will maintain its peace treaty with Israel, military says