Gary Williams has started a blog Beginning ChucK to promote learning and documentation of ChucK.
Joe McMahon is writing an OS X application using ChucK, Applescript Studio, and Perl to play and record the chimes  from the Clock of the Long Now. First version is available at the EMUSIC-L site.
Robin Davies is writing useful extension UGens. Current plans: band-limited oscillators, and VST hosting. Once Chuck's support for external DLLs is resurrected, these extensions will be posted publicly.