Hi,
From working a 5.x vcenter environment for the past 6 months and having a few 4.x clusters haven't noticed any limitations as well to be honest.
Take a look at yellow-bricks HA/DRS URL http://www.yellow-bricks.com/vmware-high-availability-deepdiv/ - the interesting piece relates to the new vsphere FDM agent under the basic's section which is new.
regards