A fairly definitive (and legally backed) answer...
Full disclosure: I have worked on this exact topic in the past and so have to be anon. :-/
With a little understanding, running Oracle RDBMS upon vSphere need not be expensive and can be very advantageous.
Firstly, you sign an OLSA. You have not signed the PDF referenced above that contains a footnote stating "This document is for educational purposes only and provides guidelines regarding Oracle's policies" and "It may not be incorporated into any contract and does not constitute a contract or a commitment to any specific terms." Thus, any partitioning guide is irrelevant.
You processor where the software is licensed "shall be defined as all processors where the Oracle programs are installed and/or running".
That, by law, is open to interpretation.
You are entitled to at least two interpretations.
How do you install software on a processor? What if there is a software tool to stop that ever happening? What if there is an audit trail?
Using simple techniques such as DRS host affinity, LUN zoning/masking (not actually required) and having a robust audit process in place you are able to run Oracle where you want and pay for only that. Then you can, where appropriate, consolidate many DBs onto said hosts and save on licensing.
Finally, go talk to the punters at the various OUGs around the world. It really isn't a problem and Oracle are in the process of shooting themselves in the foot and pushing customers away if they continue this stance.
The irony is that I really like Oracle SW. It's actually quite good!
anon.