VMworld 2008 ESX 4 beta demonstration videos:

VMware Fault Tolerance (the best HA possible)
http://download3.vmware.com/vdcos/demos/FT_Demo_800×600.html

VMware DVS (VNetwork Distributed Virtual Switch)

http://download3.vmware.com/vdcos/demos/DVS_Demo_800×600.html

Host Profiles
http://download3.vmware.com/vdcos/demos/Hostprofiles_Linked_VC_800×600.html

Original source of this info was www.rtfm-ed.co.uk