So I've just installed Sabayon 3.5. Gotta say I miss the red, but that's another story.
Basically, neither the Livecd or the finished installation showed any evidence that SL had detected my atheros chipset. I blame the incomplete ath5k driver.
Solved by compiling madwifi 0.9.4.
EDIT: Here is the thinkwiki page for the atheros card I chose for my Thinkpad t61 http://www.thinkwiki.org/wiki/ThinkPad_11a/b/g_Wireless_LAN_Mini_Express_Adapter
. That page should help more than I can.