Style: A high-quality hardwood rocker will last generations, since there are no parts to wear out. Adding cushions increases comfort. One drawback is that rockers will creep along some floor surfaces, and puppy tails, cat paws and toddler toes might get squished under the rockers. With gliders you sacrifice the conventional icon for a smooth ball bearing movement that takes less effort to send into rhythmic strides.
Durability: Avoid bargain wood rockers with glued rather than interlocking construction and rocking chairs that creak like grandma's 100-year-old wooden staircase. Remember that cherry, maple or oak wood is more durable than pine. Gliders should have ball-bearing movements, a long gliding range, and should not stick or shake during use.
Low Maintenance and Safety: Hardwood rockers age beautifully. Detachable cushions can be washed and replaced when worn. Upholstered gliders should be stain protected. To avoid scrapes, punctures and pinched fingers, moving parts of the glider should be covered and contained inside the unit. Look for a chair style that will be easy to get in and out of while you are holding baby.
Aesthetics and Extras: Glider ottomans are often optional, with gliders are priced accordingly. You may not use the ottoman in the nursery, but think about post-nursery days when you might want to use that glider in a living room, den, or office. Avoid fabric patterns that limit use and are age sensitive. Some rockers/gliders have adjustable backrests, oversized seats and additional foam cushioning.
Final Note: The most serious error lies in failing to incorporate a glider/rocker into your baby's nursery.