Stkeys USED to work before they changed the algorithm. Now the hex characters at the end of the speedtouch SSID cannot be used to derive the key. However, the key IS still produced from the devices serial number (or something like that). This reduces the potential keyspace significantly. i.e. The length of the key is known, The character set is known and the format of the serial number is known.

I am not sure I understand what you mean. The rainbow table is for a network with that specific SSID. In 'short laymans not really true terms':

WPA key=SHA1SUM(SSID+PASSWORD)

Thus we need a specific table for any given SSID (unlike LANMAN windows table). It has nothing to do with manufacturer, it just so happens than belkin, netgear etc. use their own name as the default SSID and as such that SSID will become one of the most common. In addition to this humans are predictable in their choice of SSID. How many 'skynet's and 'myhome' wifi networks have you seen?

see

and

I love this one, it is like reading a geek thriller.