The HummingBoard will have Gigabit ethernet; no word on price yet, though: http://hackaday.com/2014/04/22/hummingboard-the-vastly-more-...
Current i.MX 6 silicon aren't able squeeze out more than 470 Mbps from their Ethernet MAC.
http://cache.freescale.com/files/32bit/doc/errata/IMX6DQCE.p...
ERR004512