I don't like curtains because they always cling to me in the shower. The furnace or the a/c kicks on and blows the curtain on me. Had them in every apartment in college and hated them. Women like them because they are fashionable. Leaches were once fashionable too...doesn't mean they were good.
For safety reasons glass doors seem to make more sense to me. They give you something to hold on to getting out of the tub. Also a good place to hang wet or dry towels. So you have to clean them. So you have fewer choices in style and design. I still prefer glass over being on my a$$.