heartbeat vs keepalived for migrating IP

[Lloyd Brown <somewhere_or_other@xxxxxxx>]

I'd like to build a redundant LVS director system for my work where both 
directors have ldirectord running, and are synchronized using the 
ipvsadm --start-daemon {master | slave}.  I'd planned on using Heartbeat 
to migrate the IP address between hosts, but according to 
http://www.ultramonkey.org/papers/lvs_tutorial/html/lvs_tutorial.html, 
keepalived can perform a lot of the same functionality.  Can anyone 
speak to the relative strengths or weaknesses of using one or the other?
Thanks,
Lloyd Brown