OpenOffice Vs. LibreOffice Vs. MSOffice for academic writing
If you are in a field with lots of equations, the journals you are going to publish in will almost certainly take .tex.  So write in LaTeX.  Otherwise you will not be writing your equations rapidly or with ease (compared to those who know LaTeX)*.  Use a front end like LyX if you want some WYSIWYGness.

If you are in any non-equation-heavy field, use MS Office, for the simple reason that every journal takes .doc files and only some take other formats.  OpenOffice and LibreOffice are not yet compatible enough for publication-quality work.  (I have tried repeatedly.)  It's not that OpenOffice/LibreOffice can't do the right thing, it's that the journals only support Word.  And so either your manuscript will be full of errors that you have to hope you will catch and correct when you get page proofs, or you will have to end up using Word anyway.  Kind of sad, but that's the way things are (and have been for the past decade).

*Once you know LaTeX, everything is faster and easier, especially because you can save old solutions for formatting, shortcut macros, etc. etc., and import them with a cut and paste.  But it does take a non-negligible amount of time to learn, so if you're too impatient to learn new skills or under a very tight time deadline right now, LaTeX is not for you.  Unless you're doing equations--LaTeX still does those enough better that you may as well just use it regardless.