'pkg list -u' gives information about only those packages for which updates are available but not about those packages which are not installed.
'pkg update -nv' give information about all packages already installed , available updates and not installed.
Format of package for which are installed on latest version is :
0.5.11,5.11-0.151.0.1:20101105T053409Z -> None
Format of package for which are not installed is :
None -> 0.5.11,5.11-0.175.0.10.1.0.0:20120918T163201Z
Format of package for which updates are available is :
1.0.2,5.11-0.151:20101026T201451Z -> 1.0.3,5.11-0.175.0.0.0.0.1215:20110927T130037Z
In next line of patch , it gives current version installed , arrow sign and then latest version available if any.