I believe who ever can make a engine that works well with XE2 will have a killer engine on their hands. I am assuming xe2 is what it is cracked up to be and that with a good engine making use of fire monkey we can make good solid casual games for pc, mac and ios. And being based on work that embarcadero has created and maintain it should also be much more stable across various hardware compared to the engines we see that have been put together by single person with access to limited hardware. Any that's my 2 c worth.