I'm going to expect the additional channels without any additional price increase from Dish. Dish will not be paying more to HBO. And as I'm already paying a $20/month premium for HD, on top of the channel costs, why should they charge me even more?
The increase in HD subscribers should offset the additional satellite cost. If E* picks up another 250,000 HD subs, out of their existing subscriber base, over the next 6 months, that's $5M/month in additional revenue. It is even more if they attract new E* subs as a result of the expanded HD offerings.