2.5Gbps = NBASE-T.
http://www.nbaset.org/
5Gbps = MGBASE-T. http://www.mgbasetalliance.org/
My real world testing of 1.3Gbps 802.11ac only yields about 250Mbps of real throughput. Wifi is half duplex and has more overhead than Ethernet.
Good interview with Matthew Gast on 802.11ac