root permissions for check-update?

Hi,

Under yum-3.2.27-2.fc12, I find

   yum check-update

correctly reports available updates when run as a non-root user. 
However, with yum-3.2.28-5.fc14 on another machine, the above command 
returns no packages when run as a non-root user and returns 0, i.e. no 
packages available.  It produces the expected result only when run as 
root.  Should check-update be run as root now?

(If check-update should be run as root, perhaps it should say so to 
non-root users and return 1?  For non-root users, it currently looks 
like there are never any updates available!  That had me confused for a 
while...)

Alternatively, have I done something stupid to make this happen...?

Phil