Connecting 4 DVI (or VGA) monitors to the Macbook Pro Retina I have an existing four monitor set up connected to my PC via two video cards. If I move to a Macbook Pro retina, what is the most strait forward way to preserve this monitor set up?

These monitors are all Dell monitors that only have connectors for DVI or VGA (although my largest appears to support HDMI).
You could run 2 DVI/VGA montiors via the thunderbolt ports with adapters, and 1 via HDMI. I believe the 4th would need to be connected with a USB-to-vdeo adapter.

Check out this question for some more information:
How many external displays can I power with the 15&quot; retina MacBook Pro?