Whilst it is one thing to have a specific person gain a seat in the house of Lords, it is an entirely different one for permanent representation be given to whoever-holds-a-specific-position-in-a-specific-company.
Then again, I cant see it being significantly different (as the OP mentioned) to the position of Bishops in the House of Lords, though with a more formal representation of corporate interests in the political process, I would suspect that more stringent legislation would emerge to curtail their dominance. Perhaps something along the lines of 'the corporate lords can make contribution to debates, but cant vote' or more general limits on the contributions companies can make to political campaigns, sooner?