I've been working on some caching mechanism building quirks at the end of a dpb run, and storing all the update-info for all built packages in a locate(8) file.
The results are more drastic than I expected. I'm still fine-tuning stuff, because caching means a possibility of getting out-of-synch, and pkg_add should still recover properly, but expect *very* significant speed-ups in frequent pkg_add -u somewhere post 7.1.
