My Facebook doesn't work on Ubuntu 10.10 but works on Windows XP
"I discovered it was a problem with the MTU (maximum transmission unit), wish says the largest protocol data unit that the layer can pass onwards.
I found the answer here http://ubuntuforums.org/showthread.php?t=1376506
Hope this help others"
This helped me:
sudo ifconfig eth0 mtu 1492
ifconfig | grep MTU
Where eth0 is the type of connection that you have, and can vary from person to person.
In my case, the command needed for a wireless connection works with:
sudo ifconfig wlan0 mtu 1492
:)