Great news, although the A340-600 deal had been expected for some time. This is a trickle which I'm sure will ultimately become a flow. Cathay could well choose, in due course, to order the -500, in which case it would become the only airline to operate all four 340 models (remember they had four A340-200s back in '94/95, before the -300s joined the fleet).
Anyway, there is a thread on PPRuNET running on this; there is (as far as I can see) a slight disagreement, in that the PPRuNER states that there are 4 A340s coming. I'll have another look. The 3 A340s being leased from Boeing are to replace 3 ex Air China 340s, the departure of which is long awaited. They had no PTVs and were generally substandard, relative to the rest of the fleet. The "new" aircraft are, of course, ex SIA.