The Office 2007 suite produces documents, by default, that wasn’t compatible with older versions of Office, still widely used across many corporations. Besides, everyone just assumes that they automatically require ‘Office compatibility’, but even Microsoft do not help themselves here.
However, we forget that this suite can costs many hundreds of pounds, which makes it cost prohibitive for an individual or small business. If a friend or colleague asks you to recommend an office suite, our first thought is often Microsoft Office.