kiwifidget:chiefie:kiwifidget: OK, there is no Netflix option on my ATV2. This may be because its version is quite old? At some point it was recommended to stop ATV updates to make XBMC run better.
The two of our ATV2 have Netflix channel, check your Region.
Region was set to NZ. Changed it to US and now Netflix shows up. My Appletv2 is on version 4.3. However, Netflix wont run, it just says "currently unavailable, please try again later". Its the only device in the house its unavailable on.
You may perhaps want to do an update? I got PlexConnect running so not worrying about jailbreaking ATV2, so I updated to latest available firmware and Netflix works for our two ATV2 and the other is ATV3.