This is really lame, ever since I installed Snow Leopard which was last night, my signal keeps dropping and I get disconnected from the internet. Looking at the Wifi signal it will fluctuate and then drop. Does anyone know how to resolve this?
Try going to Network Preferences and adding a new location from the top drop down box (I named mine "Drop test"). Then I went to Advanced - TCP/IP - Renew DHCP lease. Did this after resetting the Airport router a half-dozen times.
It didn't totally solve the problem but it improved the time between drops significantly.