Delay occurs when switching between applications

System worked fine before installing Mavericks. Now each time I switch been applications there is a 5-10 sec delay before the new application responds. The applications don't actually hang, the system does catch up, but it makes the system unusable.

For example, I wil have Outlook 2011 up on one monitor and Safari up on another monitor and each application will work fine and be responsive. But when I click between the two open applications, 5-10 sec delay occurs. During the delay, the first application continues to be responsive (will respond to mouse clicks, can type, can close, can move/resize, etc.) but the second application (the one that I'm clicking to) won't respond to anything. Evenuntaly, the system catches up and the second application becomes responsive, but the same thing occurs when switching back to the original application.

So far, it seems to impact all applications - Office 2011, evernote, safari, webex, adobe reader, system perferences, and finder.

Verified Disk Permissions and vefied disk - no improvement.

Rebooted the system - no improvement.

Ensured spotlight indexing wasn't running.

Any suggestions?