As per the Naim thread cited above, Meridian seem to be hamstrung by the perception that MQA is exclusively restricted to Meridian products. I had hope that some other companies such as Arcam, named at the Shard event, might have been offering products by now so as to generate momentum. There have been dark hints of many other companies signing up but, as yet, little evidence.
Also as per the Naim thread Meridian seem to be hamstrung by a perception that their sound quality is dull, unrevealing and unexciting.