Let the dogfooding begin. Google has begun pushing Android 4.0 (Ice Cream Sandwich) to employees with Samsung Nexus S devices. While the Samsung Galaxy Nexus was the first device to sport the new version of Google's mobile platform, we expected the last pure Android phone, the Nexus S, to be the first device to get an upgrade to the new version.

Dogfooding, also called eating your own dog food, occurs when a company, generally a software company, uses the products that it makes, often before a public release.

Google engineer Adel Saoud said the following in a [now deleted] Google+ post: "Just got Ice-cream Sandwich update on my Nexus S & it's looking great :)."

Thus far, only Europe has seen Ice Cream Sandwich, with the Samsung Galaxy Nexus release over there. Those in the U.S. are awaiting the release of an LTE-supporting version on the Verizon Wireless network.

Ice Cream Sandwich is bound to come to many of the higher-profile recent releases, but not all of them. Those who can't wait can look to the developer community. Since Google released the ICS source code, folks have been working on custom versions.

The CyanogenMod team, which builds one of the most popular custom Android ROMs, has been working on CM9, the version based on the Android 4.0 Ice Cream Sandwich source code. CM9 builds are available in alpha form for the Samsung Nexus S; a beta version is available for last year's Samsung Galaxy S (not the S II).