That would depend on how you are using it and what speeds you are talking about. There are three different speeds that I can think of which you may be talking about. Your Internet/Broadband connection, wired LAN or wireless LAN.
Internet/Broadband:
This router exceeds the speed of any residential broadband connection that I am aware of. Upgrading would provide little if any difference in this area.
Wired LAN:
This router has a 4-port full-duplex 10/100 Switch built in. If your computers are wired and have 10/100/1000 NICs you could benefit by upgrading to a router that has 10/100/1000.
Wireless LAN:
This router supports 802.11b and g devices for up to 11 Mbps and 54 Mbps respectively. You could upgrade to 802.11n which most...