Metallic wallpaper can scratch just like metal. Watch out if you have pets or kids. The same holds true for papers with a super-matte finish: Too much hands-on contact can mark them up. Flocked papers can get dusty. Use the soft-brush attachment on the vacuum. (Of course, make sure the brush is clean first.)
Grass cloth adds depth and texture without any pattern. Decorators love it for bedrooms.
Steam and water are hard on wallpaper. In a kitchen, don’t hang wallpaper near the sink or the stove. A bathroom that has a shower or a tub will age paper faster than a dry room will. (You might want to paper a powder room instead.)
Crooked old houses with walls that are less than straight look best with busy patterns, which hide imperfect corners. Linear designs (like stripes) only emphasize the trouble.