There is a "R integration" with nodes in a directory "R" that is directly below the root of the node repository. And then there are further R node libraries e.g. in the community contributions.
Who are the contributors?
Which nodes do you prefer, i.e. where are the differences?
IMO the newer R interactive nodes are the best thing since sliced bread. They permit you to debug your code right in R without ever leaving KNIME, no configuring and running of the node required. Additionally, they allow you to save snippets in a template library, which used to be the edge that the Community Nodes had over the older, built-in solutions. The standard nodes come in local andserver variants, but they are neither interactive (configure and run nodes even for code testing) nor template-powered.