[ros-users] Should I write plugins for rqt or rviz?

I'm writing some GUI plugins for visualizing data coming off an Arducopter,
and after looking through the docs and release announcement for Groovy, I'm
not sure which library I should be writing plugins for. Is it recommended
that plugins be written for rqt or rviz? And are there any tutorials for
doing so, for the upcoming Groovy release?

Thanks!
Christopher