First of all, thanks for this usefull howto (Although i didn't switch yet to Lion!, I prefer SL)
Like everybody, I was worried about native Wi-Fi support on Toshiba L500 series.
Genuine Wi-Fi chip (RTL8191SE) don't seems to be supported yet.
Then, I swap cards, and installed an Atheros AR5008. Unfortunately, Bios silently discarded my card (whitelist), and unpowered it.
I had two options, cover pin20 of my card (to ignore power/unpower signal) OR extract/modify BIOS whitelist. I did the second option and it work pretty well now!
For tech guys, withelist is located in BIOSCOD02.ROM, between offset 49F0 and 4A20.
By the way, here is the complete whitelist for Toshiba L500 series, this could be usefull to change your wificard without trouble... And good news, some Atheros cards are listed
168C:002A (Atheros AR928X)
168C:002B (Atheros AR9285)
8086:4235 (Intel WiFi Link 5300)
8086:4232 (Intel WiFi Link 5100)
8086:423C (Intel WiFi Link 5150)
10EC:8199 (Realtek 8187SE)
10EC:8192 (Realtek 8192SE)
10EC:8172 (Realtek 8191SE)