How many monitors can the 13" retina MacBook Pro output to? The 15" retina can do three (and itself) via daisychaining two Thunderbolts (or just using the two ports) and with the HDMI port. Is the 13" retina able to do this as well?
You can drive 3 including the internal on the 13". However, you cannot run 3 external displays even if not using the internal.

source: I have one and have tested this.