i call people in that position "frenemies". often times in the large enterprise space, even your largest rivals have something you want/need, whether you like it or not.

sometimes it is writing software that interoperates (bi and the like), other times it is direct need (java in the case of google and oracle, and i'm sure at least some backend systems).

Google wants faster CPUs that use lower power and don't cost too much to be used in their server farms.

Sooner or later they will port Android to it so it can be used in smart phones and tablets.

We were speculating as to why Oracle would be interested in getting in bad with these guys on this architecture, specifically. Google is if anything an opponent of Oracle, so I assume Oracle's reasons for getting involved are somewhat different than what you've outlined.

It makes sense for Oracle to keep a close eye on new architectures that seems like it may get some traction. If it makes it into the server space, it'll affect them.

Given all the flap about HP & Oracle over the Itanium servers and Mark Hurd, I'm not sure HP is on Oracle's Xmas card list.

It occurs to me that Oracle has a Java business, and Google has an Android business.

It's important to keep Intel on their toes.

Intel's a sponsor too.

Intel also has an ARM architecture license (allowing them to design their own ARM cores).

Being involved in alternative architectures seems like a sound defensive move.