There has been a lot of debate lately on whether or not hosiery can be a replacement for trousers. Some even went as far as to create a website (tightsarenotpants.com) to express their views.
As for me, I'm perfectly fine with leggings/tights as leg coverings in day-to-day life as long as you cover your ass. Seriously. I've seen nice behinds clad in only spandex, but it seems too obvious. You're bragging about your butt. And while dudes may appreciate it, do you really want that kind of attention? The callipigious among us can tastefully flaunt the goods in a pencil skirt or well-cut trousers. And then there's the bad. The not-so-nice rear-ends that are dumped into (usually) pale-colored leggings that reveal every little lump and are (usually) positioned in my direct line of vision. Me, on a seat in the subway. You, standing across from me with your back to me. So please, cover your ass and leave some things to the imagination.
Other booty-flaunting options:
1. Silk skirt or dress cut on the bias. Always curve-enhancing.
2. Fitted pencil skirt. (as seen above from american apparel)
3. If you're going with high-waisted pants or shorts, look for a back yoke or some sort of seaming above your butt and below the waistband. The tailoring helps the fabric pull in at the right places to make it look like your behind pops out more.
(as seen above by lux)
4. Shiny or metallic fabrics, butt be careful! The potential for tacky is great. Look for a subtle sheen.
5. Well-tailored pants. Look at the profile. If they follow the curve of your rear around to the base of your butt, then they're winners.
6. High-heels. They shape the muscles in your legs and butt like magic.