Yes, it does, as long as you have an HD receiver. (So, those using really old SD-only receivers would not get it, until they upgrade to a newer receiver.)
Yes, although even that would not get you the Gallery if you are using a Wally, since the Gallery app is missing. Gallery requires a Hopper (any model Hopper) in order to get the app. Wally users do get the Gallery content through the On Demand menu during free previews, though. I am not sure whether that would work if they were paying the $5, or if Wally users even have the option of paying for it, if there is no Hopper on the account.