Solution to those particular WebOS loads that cannot activate wifi for activation:
1) Charge the TP fully overnight, it must be at 100% charge
2) UNPLUG the TP (it won't send wifi chipset wakeup if it's plugged in)
3) Turn on LCD to activate via setup process. The Wifi lists show NO routers for the models with this problem.
4) Turn off LCD via tapping power button.
5) Wait one minute
6) Turn on LCD; TP will say "wifi is off", it will come alive and ALL routers will suddenly appear.
7) Quickly choose router and type in WEP/WPA/WPA2 key.
8) TP should then activate and wifi will stay one as long as you don't turn it off!
9) Not a permanent fix-- if you turn off wifi it may not activate again (it may momentarily show you routers but won't associate, then all routers disappear from screen).
I tried activating my two TPs for days and thought the wifi chipset was dead (I picked up NO routers among the dozens around me). This was the solution to activate. I still suspect a batch of bad wifi chipsets or a bizarre pre-install settings that persists between WebOS upgrades.