Other than the obvious part of hopefully the break will allow Steve to come back stronger for more time at the healm, this could be seen as an opportune time for Apple, Steve is still involved in the major decisions but it we are looking at some non Steve time at Apple and hopefully all going well the stock market will come to realize that there is more to Apple than Steve Jobs.
It is also good that this period of time happens when Apple itself is in a very healthy financial state, plenty of cash in the bank & next to no debts, the leadership team isnt under extreme pressure to turn the company around or in a situation where making one decision could see the company fail.
Good luck to Steve and lets see Apple show everyone that one person doesn't make the company.