I had issues immediately after the update and reboot. Programs were hanging left and right, and the system wouldn't respond to commands to shut down or restart. After a forced restart everything seems to be working fine.
This.There was an initial lag for the first minute or so while the system re-indexed itself.
This.
After a system update, Spotlight will do a reindex.
That's really weird. I tried mine and it worked. Have you tried restarting the computer again?
If you're having trouble with the regular update, try downloading the combo update. Installing the combo update over the regular update can sometimes fix issues.