The Jumperoo by Fisher-Price is an excellent system for babies who have yet to learn to walk or crawl. It is an improvement over the old doorway jumpers because it is on a freestanding base, thereby eliminating the risk of jumping into the door jamb.
I like the idea of having a jumper for my baby. It increases leg strength and balance. It is also a safe place for me to put him while I'm cooking dinner.
There are lights and toys mounted on the front of the jumper, and lights light up and music plays as the baby jumps. These can be turned off, and there are two volume settings which is nice.
It takes up a fair bit of space, which is the main drawback. I also sometimes have a difficult time getting both of my baby's legs through the seat without putting both feet through one hole, or folding his foot underneath him.