He is trying to play it a low profile till he is able to come to terms with the role. Once its done we would be able to judge him better as now its too early to do so!!

Ratan Tata did not make much of an impression when he became the chairman. In fact his only plus point for becoming a Chairman in 1990 was that he was a member of Tata family. The divisions he had headed till then like Nelco were failures and had to be closed down. In fact some of the successful members of Tata's Board like Russi Moody. used to openly criticize Rattan. It took nearly 8 years before Rattan managed to establish himself. In case of Rattan he had the advantage of being projected as JRD's successor much before he became the Chairman. In case of Cyrus Mistry he is an unknown figure who was in the shadow. He must be a worthy successor otherwise he could not have made it to that post in a professionally managed company like Tata.

He is now is learning process and may be succeed his predecessors well

Yes he will be and it is too early to make any visible impression

One good thing with TATA'sis they r good in selecting their successors.
Ratanji wasn't hvng any track record at all when he was chosen by JRD, and many ppl. raised their eye brow but he proved to be excellent.
I new one also will further expand their empire, though he is from outside the family.