It would increase his own options in terms of a landing spot, though, and would give the Blazers a chance to get something of value, potentially, in return. Theoretically, all teams could make an offer for Oden at the deadline, while only a handful with cap space will be able to in summer 2012. So, while he can veto a trade, if the trade makes sense in terms of his future, and it gets him a contract from his new team, it would be dumb of him to veto it just to limit his options as a UFA.
Again, this all depends on these being the same as the old CBA, but if traded on his QO, he goes from bird to non-bird free agent. So it wouldn't make sense for him, because he would either need to go to a team with cap space, or would be looking at the MLE, or same group of cap space teams. By losing his bird rights free agency, he loses his biggest chance at a big contract, and thus would likely veto any deal brought to him.
I would like for us to be somewhere around 23-30 million on the hook for the next 3-5 years; with the final year being a team option.