From what I've understood, Sun didn't license everything to IBM (or for that matter, to others as you stated). Charles Nutter had a great post (and it has been updated) on the Oracle suit against Google where he talks about some of the wild claims that Oracle was making:

http://blog.headius.com/2010/08/my-thoughts-on-oracle-v-goog...

My point is that no rational company would attack its own base. Oracle had some wild claims. These will be toned down and they will come to an agreement. Things will move on.

I'm not saying that people shouldn't pay attention to Oracle's antics (even though I just consider Oracle a whining child at this point), but I think this whole thing is overblown.