I don't see why the DemocRATs' mounting this filibuster (whether it's called that or not) doesn't already set that precedent. A cloture vote would at least make the RATs go on the record as supporting this filibuster.
I agree with you, but I think that is what is behind this - neither party wants to have the "filibuster" arrow removed from their quiver.
If it were my choice, I would force the vote and then bring suit and push it up as quickly as possible to the Supreme Court to determine whether or not filibusters of judicial nominations are indeed unconstitutional!