The regional sports networks are 24x7 in SD on Dish, and then they pick the games that will fit into the 8-10 slots they have for HD games. The decision over which games to broadcast in HD is made on a market by market basis, presumably based on expected ratings or some other kind of selection system.Last year, Dish's idiotic way of "sharing the love" for their limited HD capacity was to broadcast several games with 2 HD and 2 SD (home and away) versions each, while other games had only 2 SD (home and away) versions each. In most cases there were HD broadcasts available for the games Dish chose to show only in SD.
The bottom line is they pick which markets will get to see their game in HD, and then from there the games make it into the NHL Center Ice package, which is why you get games where both the home and away feed are in HD while other games are SD only. When there isn't a programming dispute, there is nothing special uplinked for Center Ice, they just instruct the receivers to map to the existing regional sports networks for the game. That's why you typically see the commercials from whatever market is airing the game.
The limited feeds for CI so far is due to the FOX Programming dispute. The NHL provides SD feeds of every game to providers offering the Center Ice package, but the NHL only provides 1 feed per game.If CI continues in it's current format of one broadcast per game (home only), that should free up a lot of bandwidth for more HD broadcasts this year. But based on their broadcasts last year, I don't know if Dish can figure this out...
Dish and DirecTV generally skip using the NHL SD feed and simply authorize the receivers of Center Ice subscribers to show the out-of-market RSN broadcast for the duration of the game. Dish is at a disadvantage right now because they don't have the FOX feeds, so they can only air the CSN / PrimeTicket games in HD, or they have to fall back on the SD feed they get from the league.
So far on DirecTV about 95% of the games have had both home and away coverage in HD on Center Ice.