Might be a few hiccups in the near future but no plans to actually shut the project down completely.
http://www.primegrid.com/forum_thread.p ... 065#138477
Michael and Jim are stepping down from running PrimeGrid and are looking for a team to take over (apparently it's a LOT of work!)
Everything is done remotely (servers are in Lithuania) so you'd need a good internet connection and (probably) a high data cap.