Everyone that knows LaTeX loves it; mostly for it taking care of document formatting (letting you concentrate on writing) and producing beautifully typeset equations.
Once you've learned LaTeX, it's good to go on to the next step. That would be Lyx. Lyx is a graphical interface to LaTeX, and frankly, you have to use it to understand how much of a time saver it is. Writing LaTeX documents / research papers will never be the same :-)
Those with Macs can now fetch Lyx 2.0 Beta 1. See the feature list. Windows binaries are sure to follow.
My favorite feature of Lyx 2.0 Beta 1? Spell checking on Macs works out of the box!