For those who are inclined to try such things, 2.1.1-PRERELEASE snapshots are up for testing at http://snapshots.pfsense.org/

Update URLs for use in firmware update settings:

http://snapshots.pfsense.org/FreeBSD_RELENG_8_3/amd64/pfSense_RELENG_2_1/.updaters/

http://snapshots.pfsense.org/FreeBSD_RELENG_8_3/i386/pfSense_RELENG_2_1/.updaters/

The current set of builds have the new Intel drivers for em/igb/ixgb/ixgbe (Thanks Ermal!) and should support i210 and i354 and others, and should hopefully fix issues that have been observed with ixgb/ixgbe drivers. [EDIT: These drivers were causing major issues and had to be backed out. Support for those chips will have to wait for pfSense 2.2]

Give them a spin, especially if you have hardware that could benefit from the new drivers.

A list of changes between 2.1 and 2.1.1 may be found here:

https://doc.pfsense.org/index.php/2.1.1_New_Features_and_Changes