Given it takes almost no effort to copy Bitcoin and release a variant, given it takes almost no resources run the ledger and mine and given that the only thing that all crypto currencies really lack is a certain amount of credibility and brand awareness, will 2014 be the year that big corporations release their own Crypto and what will this do to Bitcoin?
For a corporation to profit they'd want to start with a large stash of the currency. You need incentive for individuals to participate or else you are just running your own network.
Just look at Ripple. 80% of XRP belongs to a select few.
Besides the major strength of Bitcoin and other Crypto currencies that employ proof of work is that it is more resilient to Byzantine attacks.
I must admit I haven't really looked into the Ripple code but forming consensus where message generation may not be as time-bounded as in a PoW model might put them at a classical situation where 3f+1 correct nodes are required for f byzantine nodes to guarantee correctness. This of course may also apply to other systems (pure proof of stake model?). It makes sense to have slow block creation on the chain because it gives the network enough time to disseminate information which strengthens the model.
Back to your assumption: Sure, corporations may run their own digital currencies as they are already doing but unless they can give individuals a strong incentive to participate it will always be closely linked to what that corporation offers