>For example, Eric Schmidt is apparently a super nice guy [1] Larry Ellison on the other hand, has cited (I believe, Ghengis Khan?) "It is not enough that I succeed, everyone else must fail"
See, while I think that would make it /much/ harder for a little guy to go up against ellison than agains schmidt, being as oracle is /smaller/ than google, I don't think aggression is enough to tip the scales.
the thing is, aggression only helps you if you have the ability to take down your enemy. I don't think Oracle has the ability to threaten google's core revenue generating stuff, search, adwords and adsense.
Oracle is an enterprise software company, and google is a consumer software company. Completely different markets. I think either one will do poorly breaking in to the other's market.
my point with the rdbms is that there's something relatively simple (well, relatively simple if you have Google's Engineering resources) google could do to hurt oracle. Now, obviously, for it to really hurt Oracle, it'd need to be marketed by companies that can market to the sort of people who spens money on Oracle, e.g., not google. but, if you release something awesome under a loose enough license, that's what happens. Other people will take the tech, relabel it, and start selling it. Look at all the companies that took ZFS and started selling network-attached storage devices. (granted NetApp is now using it's patents in an attempt to stop that sort of thing... like I said, there would be a legal shitstorm... but it is cutting in to NetApps core market.)
The interesting thing about just releasing a RDBMS is that it's a not-very aggressive, very nerdy way to get revenge. it doesn't require Schmidt to talk about blood or anything, just releasing some really cool new software.
Now, it would be really hard to actually kill oracle, but hurt it a little, in it's core business? yeah, I think Google releasing an open-source, loosely-licensed Oracle-quality and scale RDBMS under a permissive license would slowly do just that. Hell, I've personally watched managers debate Oracle vs MySQL... and many of those debates were close. many more would have ended up on the MySQL side if Oracle didn't have some significant technical and reliability advantages.
My understanding is that Google's core business and nearly all their revinue comes from adwords, adsense, and search. My understanding is that everything else is just fucking around- e.g. gmail doesn't make them money (this may be wrong these days, but gmail is certainly small potatoes compared to adwords and adsense.) There's no way Oracle could put a dent in google's dominance in that area. Just like google wouldn't be able to market to enterprises like Oracle does, oracle doesn't know how to sell to consumers, technical barriers aside... and for Oracle, the technical barriers would be enormous. Oracle is used to customers willing to go spend an order of magnitude or two over the cost of commodity disk on storage. In the search market, you have to very carefully write your software so that it can work okay even though it is running on the cheapest and least reliable hardware you can find. (One of my past jobs was dealing with the flaky hardware at one of the larger search clusters.)
I guess my main point is that I can see how google could contribute to others chipping away at Oracle's core business... I don't see how Oracle could contribute to anyone chipping away at Google's core business.