Did someone already mention the wider length between a women's hips as compared to a man's? It puts much more stress on the knees and joints and such. Running is the #1 injury sport for women (perhaps also because it's also the most popular?) but I remember telling my running friends that their shoes were wrong for them. Women's running shoes are just miniaturized versions of men's shoes.
EEEGH. Wrong, the shoes have to be made to handle the different impact hitting the ground has on a woman's body as opposed to a man.
Even 4 or 5 years ago, I don't think anyone in mainstream running shops knew about this. We went to a specialty running shoe store in a 'big city' and the fitters/salespeople didn't know what I was talking about.
Of course, this made my ISTJ friend roll her eyes and think I was coming up with more 'crazy CzeCze information' again. Sonuva.
Perhaps someone already mentioned this, in which case I concur.
And I have heard trail running (in the woods, on dirt) are much friendlier on the joints. And probably more meditative as far as the scenery. Running on the beach (I know, not really "running") barefoot is a great work out as well!