I've noticed that the size of a docx file is now almost 3 times smaller in size than the corresponding pdf saved in Word 2010? Is this something MS is doing consciously to prevent people from saving in PDF?
1) depends on content - is this just text with some formatting? Does the PDF embed fonts? Are there images? Etc.<p>2) docx format is wrapped in a zip file, so there is built-in default compression; PDF is not compressed by default<p>3) does it matter? Most documents I see these days are <1 MB; assuming that universal compression ratio of 3 is achieved, the PDF file would be 3 MB large - not very significant in absolute numbers.<p>I'd say it's not a conspiracy, just a different format - and that the size difference is not very significant.
(Now, a 200 MB docx versus a 600 MB pdf might be significant; but if you are routinely handling 200 MB documents, I'd suspect Something Is Horribly Wrong anyway).
This is actually relevant, though it may not seem so at first glance. The ratio between well-compressed and not-compressed document types declines as the quality of the writing improves.<p>Obviously one of these document types routinely uses compression. If the user composes prose carefully, and avoids repetition, the contrast you cite may be much less.<p>The gold standard for compressible text is political speeches -- they tend to say almost nothing with as many words as possible. I've always thought part of the decision process leading to voting for someone should include an attempt to compress his speeches.
I don't think the idea behind offering you the PDF option is to "prevent" you from using it....<p>In fact, it was Adobe that tried to prevent you from saving to PDF. It threatened Microsoft with legal action (especially in Europe) for trying to offer the "open" PDF format in Office 2007. This was widely reported at the time, but see, for example:<p><a href="http://betanews.com/2006/06/02/adobe-to-sue-microsoft-for-pdf-feature/" rel="nofollow">http://betanews.com/2006/06/02/adobe-to-sue-microsoft-for-pd...</a>