VMware has released a KB with a handy vmfstools command to check your VM’s disk status.  If the VMFS output shows a “Z” it is Zerothick with blocks that have not been written to yet.
Read the article here.
This allows you to check the disk status for options such as Fault Tolerance or Microsoft Cluster Services.  [...]

VMware has acknowledged an issue that we have been battling for some time with a Pegasus CIMSERVER memory leak.  It has been fixed under ESX 4, as it does not use Pegasus, otherwise setup a CRON job for restart Pegasus periodically.
This issue has been extremely frustrating in our environment for a very long time, and [...]

You will find these instructions in other How To posts and links here, but I thought I would post a simple KB from VMware for quick reference.  service mgmt-vmware restart, will NOT cause a Guest to reboot or go down.
Click here for the article.

8 new patches have been released for ESX 3.5 only.  These do not apply to ESX/i 4 or older versions of ESX/i 3.x.
ESX350-200908401-BG – General
ESX350-200908402-BG – Critical
ESX350-200908403-BG – General
ESX350-200908404-BG – General
ESX350-200908405-BG – Critical
ESX350-200908406-BG – Critical
ESX350-200908407-BG – General
ESX350-200908408-BG – Critical

VMware has posted a new KB with some useful quick troubleshooting for slow storage issues.  I personally use DAVG/cmd frequently with our Fiber DMX infrastructure.
Check out here.

VMware has released ESX 3.5 patches.  6 Patches, 4 are Critical.  KB1012543 is most interesting overall.  Hit the jump for links and more information.

Good article about troubleshooting Hostd (mgmt-vmware) issues.

find -iname "*-flat.vmdk" -mtime +7 -ls
you could identify vmdk files older then 7 days that have not been modified and are either off or orphaned.
or
find -iname "*-delta.vmdk" -mtime +7 -ls
to find old snapshots