Where are the best places to register for baby stuff?

We're not registering yet, but it's fun to start looking

I couldn't find any recent posts on this, so I wanted to know where everyone recommends registering for a baby shower (or just for baby stuff in general).

Did you have good registering experiences anywhere? Did you have bad registering experiences? Which places have good registry incentives and return policies? What places do guests prefer? How many places do most people register?