I ate at T-Rex the weekend after it opened. We were underwhelmed, to say the least. As another poster stated, if you have eaten at Rainforest, you've eaten at T-Rex. I had a steak, which was marginal at best. My wife had a shrimp dish which she said was good, but nothing she would want to go back for.
Honestly, T-Rex is the Six Flags of themed dining. It's big, loud, overdone, and mediocre quality. Once you've done Disney themed dining, nothing is ever the same.