Some fields might prefer one product over another. For instance, there's a lot of LaTeX use in math and physics. But you'd probably already know if you needed to use LaTeX.
Any academic field can benefit from using latex (though go for xetex output from the start for the otf/unicode-support). I'm a linguist and beside all the other benefits, glossing (via the covington package in my case) has been a lifesaver. Also, anyone on any computer/OS can have a look at my working file as it's a simple plain text document.
I couldn't go back to a word processor even if I wanted to. Another benefit is that you can use a good text editor as your front end, having numerous "text crunching" tools and powerful shortcuts available.
Scrivener (or Voodoo Pad) seems like a nice working tool, regardless.
To the OP: latex does all you want to and much, much more should you ever need it. There is a bit of a learning curve to it but in return it's all free and very powerful.
Your choice of front end/text editor might not be free - I use
Sublime Text 2 (beta) - but there are a lot of free alternatives out there such as TexShop, which is included in
MacTex or
Texnic center - it should be noted that I haven't used either.
There are also dedicated native editors starting to pop up such as
Texpad (not free - haven't tried) and
TeXnicle (native and free? - though, the 2.0 beta crashed when trying to open my thesis). You'll still have to download a latex installation, but that's free.
For a more conventional word processor, perhaps try the
Mellel demo as it seems to be tailored for academics and has great language support.
Sorry for the latex preaching. Have fun, whatever you end up with.