Sony introduced on the market a series of Wi-fi Ready Bravia models that work with USB WI-FI adapter or USB Dongle. In USA the WI-FI Ready models are shipped with USB Dongle included, and after the information from the support page it is a Linksys product and not Sony.
In Europe these Wi-fi Ready models don’t come with the USB Dongle included, you can use any DLNA certified WiFi adapter or modem with the TV. You can also buy USB Wireless LAN adapter from Sony, model name: UWA-BR100
If you have problem with the Wi-fi adapters or USB Dongles let us know in the comment field.