There are many initiatives of using solidity as a blockchain programming language not just in Ethereum but in many other mostly consortium blockchain solutions. On the one hand, this is a logical direction, as most of the developers who has blockchain programming experience have the experience with solidity - Ethereum. On the other hand, most of the existing blockchain applications are realized with the help of Solidity so they might be migrated this way to a consortium platform without any modification.
Despite the direction is perhaps not absolutely optimal. On the one hand, Solidity was one of the pure Blockchain oriented programming language and certainly it is good for a first initiative but it is perhaps not so optimal on a long run. It has several "child illnesses" that should be repaired on a long run, like the chaotic type system or payment functions. On the other hand, programming on Ethereum with Solidity supposes indirectly very strong constraints in terms of computation and gas. If the same use case is put on the top of a consortium blockchain, where gas is practically free of charge, the application should be implemented probably totally differently, even if the programming language is the same.