Big YEAH! for Microsoft on this. Sure it's limited to just the phone but it's free and a big step forward for Microsoft in trying to move Office forward without diminishing the need for W8 tablets. Let's hope they release the Android version soon. (Though with the current relationship between Microsoft and Google I doubt we'll see this any time soon.)
IMO the goal should be to keep people buying Office and keep them in the Microsoft ecosystem. They just need to adopt the BYOD concept and let Windows devices sink or swim on their own.