Yup, my first thought too. Though presumably different roots - player and pliers. There's also another stringr (crowdsourced video content platform) and caret (text editing for Chrome).
Why is it that popular libraries in R are replaced with other names when enhanced? I.e., plyr->dplyr, reshape->reshape2, etc.? Is it a namespacing thing? I guess if there's not a universally accepted way of versioning library imports that would explain it as well.