This is important: Microsoft has been busy getting their version of the office XML standard written (basically an open format for storing documents like excel spreadsheets, power point presentations, and word documents). However, it seems they got in a little bit of a hurry and really screwed up the mathematical formulas for spreadsheets. What does this mean? Left uncorrected, data stored in this format would return incorrect results – really bad news for anyone storing important information in their spreadsheets. And we don’t know anyone who does that, now do we? Read this. Sounds like ODF is still the best choice. (via)