Siri-XM is the poster child for why this shouldn't happen. After their merger prices went up, quality (playlist wise) of the channels went down, and there has been close to zero as far as new hardware offerings and innovation. Hell, three years after the merger and you still can't put a Siri and XM radio on the same account, you have to have two separate accounts and pay full price for both.
The only thing that has come to subscriber's benefit is the fact the Sirius/XM is now very easy to get a discounted subscription. I.E. I have been on the 5 months for $20.00 for about a year now. If they won't offer it anymore...I guess I don't really need the luxury of satellite radio.