Some people think that Tata will bring investment and new models. So thats a good thing. Many brands get bought out. I think Jaguar has a strong tradition that should not be damaged by this.
Othes may differ, I'm new to Jaguar ownership.

 

So far Tata has approved all designs and projected models to continue as planned. Tata seems to be letting Jaguar do its thing. At least for now, I don't think Tata will have any detrimental effect on Jaguar. Tata really only wanted Land Rover, but Ford would only sell Jaguar and Land Rover as one. There is rumor that Tata might sell off Jaguar as a seperate company. Who knows in this world of constant quick change!!

 

Jaguar and Land Rover will stay together
They share to much technology and even parts
one without the other would not be benificial for anyone
at least thats how it is now
in a few years....? who knows