The Carrier IQ smartphone tracking scandal continues to grow, but we've just learned some interesting news from an extremely reliable source: the Google Nexus One, Nexus S, Galaxy Nexus, and the original Xoom tablet do not contain Carrier IQ software. Each of those devices was launched in direct partnership with Google as the flagship for a new version of Android, so it seems that the addition of Carrier IQ comes from OEMs and carriers after Google open-sources Android's code. Carriers requiring manufacturers to include Carrier IQ would also explain why references to the software have been found in iOS — Apple works much more closely with carriers since it builds both the hardware and software of the iPhone.
All that said, we're still wondering why Google would reject Carrier IQ from its flagship devices but allow phones with the software to pass the various Android compatibility tests required to license its apps like Gmail, Google Maps, and Android Market. (Google's Andy Rubin has issued emergency "stop ship" orders to Samsung and Motorola for including third-party Wi-Fi location software in the past, after all.) We're also still wondering exactly what data Carrier IQ collects and exactly when and where it sends that data — if it sends it at all. We're constantly digging for more info, but for now it seems your safest bet is to avoid the issue entirely and go with a Nexus.