I could probably do without MS Office completely and use something else as I no longer have to worry about sending documents to people that effectively required it to be in Word/Excel format.
I tried Open Office v2 and didn't like it in the slightest and though supposedly compatible it did screw with my documents, even when they were only opened it asked if the changes should be saved. I haven't tried the latest version of OO, but my need now for word processing and spreadsheets is very limited, so I have stuck with what I have.