For those who wonder about bandwidth usage during gameplay in CS, see my home router traffic graph below. The itsy bitsy spikes at 8pm-9pm Friday, midnight to 1am today and again at 4pm today (the blue line) is me playing on meat hook. As you can see latency is everything as the game only uses around 24Kbit/s of bandwidth!
(http://plug.crosswired.co.uk:24001/host-eth0-day.png)
its a live graph so if you cant see the spikes its cos they happend saturday 15th :-)