How long does it take to get from Penzance to Land's End by car? Might give the ferry a boost as the travel time from Penzance by sea becomes more competitive compared to a car/flight combo via Land's End, given the much cheaper ferry fares.
The other aspect that surprises me is that I fail to see the competitive edge for BIH from Land's End. At the moment, it is more convenient to depart from Penzance for almost all travellers, be they tourists, locals or businessmen. From Land's End, Skybus will be quite a bit cheaper as they operate planes rather than helis, won't they? (Or are the high operating costs indeed off-set by the larger capacity of the heli?)