Ran cbcollect_info on 2-node cluster while load running, but I didn't see ay ns_server:debug messages in the ns_server.info.log file. I was running build 2.0.0-1827_rel on linux-vm.
[
jenkins@cen-1722 cbcollect_info_20121010-190218]$ grep debug ns_server.info.log
{loglevel_default,debug},
{loglevel_ns_server,debug},
{loglevel_error_logger,debug},
{loglevel_user,debug},
{loglevel_menelaus,debug},
{loglevel_ns_doctor,debug},
{loglevel_stats,debug},
{loglevel_rebalance,debug},
{loglevel_cluster,debug},
{loglevel_views,debug},
{loglevel_mapreduce_errors,debug}]
'sink-disk_debug','sink-disk_couchdb',