Plugin developers who want to take advantage of these performance improvements have plenty of time to prepare an updated version to have on deck to coincide with the 2.0 release.

you gotta be joking right? alot of buddypress plugin developers take long enough to update and fix bugs that are already exist within their plugins without upgrading them for the launch of a new buddypress release, after reading the buddypress trac about 2.0 i really cant see this upgrade going very well for many upon its release, those people who have buddypress running nice and smoothly will most likely upgrade and find lots of their plugins break and will most likely lose functionality that there users expect until the plugin devs get up to shape (in some cases if at all!)
this is why i believe buddypress needs to think of backwards compat with as many bp plugins as possible rather than say hey leave it to the devs of the plugins and hope they react quikly!

well sorry if it sounds like im bursting your bubble but just watch and see upon its release, im not just talking about free plugins im talking about ones people have also paid for. its allways the same on any major update!