Same message sent to UK cardholders, see 13Aplha's post above.
25% tier points on discounted economy tickets. So assuming you still get 40 points for a European economy return you'd get 10 points for a discounted ticket. So that's 60 discounted returns for a Silver card, 150 for Gold. Would that influence a customer? Think not.
But the message refers only to discounted economy. Earlier this year when they were offering a similar deal short term I got full tier points on discounted Club Europe. And (amazingly) full tier points on an AirMiles (not BA miles) redemption. So perhaps there is an incentive for business travellers on a tight budget after all.