Given some recent discussion with a moderator (not sure if I should name names?), I just wanted to highlight that post given I've found it pretty useful -- useful enough I wrote up my own summary to have handy whenever I get into NFS discussions with customers -- here's my summary as well (full credit goes to the post above but thought I'd put it here as well in case helpful for anyone).
Ranking these in order of importance....
Deduplication - possible to use deduplicated space savings with LUNs but MUCH more complicated (have to mess with fractional reserve, LUN thin provisioning, etc. -- possible to get caught overprovisioning and have real issues)
VMware Datastore sizing -- easy datastore growth (possible with VMFS) and shrinking (not possible with VMFS)
Larger datastores - no need to keep datastores smaller like with VMFS - up to 16 TB
Snapshots - can retrieve individual vmdk's from snapshots and/or mount vmdk's from snapshots for single file restore
SMVI - main benefit is ability to do faster VM restores (uses SnapRestore rather than LUN clone so can instantly restore a single VM to any previous snapshot)
VMDK Thin Provisioning
Ease of addition - somewhat easier than LUNs/VMFS
VMFS/RDMs - no need to deal with them
Single-file FlexClone (future feature) - can clone a vmdk instantly for fast provisioning
No single disk I/O queue as with iSCSI/FC so performance limitations are purely governed by pipe size and disk array size.
Faster failover to SnapMirror remote copies (less steps plus faster steps) - no need to do LUN resignaturing
ESX server I/O is small block and extremely random meaning that bandwidth is less important (i.e. GigE works well).
Can dump individual VM's via NDMP
No FC zoning, switch cost, HBA's, compatibility matrices, or LUN IDs