A couple of weeks ago PhysOrg.com had a post about how dogs drink. It seems they use the same technique that cats do, and it's quite a complex action. There's a clip showing a slow motion x-ray view of a dog drinking.
The description of the action says the dog creates a column of water from the dish, and then closes her mouth, trapping the water. I think it's more clearly visible in this slow motion video. When I saw this clip, some years ago, I thought there was a kind of vacuum, but now I do see how the dog traps water. It appears that it takes three laps before any of the water reaches the throat.
In this clip we see another dog drink, but I also enjoyed the human trying to drink like a dog!
In this one you can clearly see the column of water rising to the dog's mouth.