If you do not remain alert to what your players are thinking, action around the table can slow. If everyone stops talking and looks at you, you need to jump in and ask what the players want to do next. Your questions tell the players that something is expected of them.This is the first DM advice in the first module of 4th Edition, and it's rubbish. Actually, it's the first DM advice in 4th Edition full stop, as Keep hit stores before the Player's Handbook. Let's try rewriting it.
If you do not remain alert to how your players are responding to the game, action around the table can slow. If everyone stops talking and looks at you, you need to jump in and provide some new events. When your players aren't actively interacting with the game, it tells you that something is expected of you.This will make a better game. As a side benefit, it removes the suggestion that the DM should be telepathic.
"What do you do next?" is the trademark question of the bad DM. Firstly, it implies a situation with too many interesting options, or not enough. Research shows that humans prefer to choose from two alternatives rather than from many. As DM, it is your job to narrow the options down to two equally intriguing possibilities through storytelling, and, if the players have trouble deciding, introduce an event gently nudging them towards your preferred path.
The other reason it's a bad question is it means the players have become static. They are somewhere where they are, at least for a moment, "just fine". Players should never be "just fine" - they should always be within sight of "just fine", but never quite there. There should always be something that they just need to check, or someplace nearby that is ever so slightly better than where they are.
Keep on the Shadowfell starts with the players ambushed by kobolds while on the road to Winterhaven village. At the end of the fight, asking "What do you do next?" is not helpful. The players are obviously intended to continue to Winterhaven, but there's no obvious reward to them in doing so other than the continuation of the story.
You need to introduce a short term goal that tugs at the players' greed, self-preservation, or curiosity.
For instance, you could add to the loot a small gold bracelet, and mention to the players, "You don't know how much it's worth - but you could probably find out in Winterhaven." You could say, "With kobolds attacking travellers this openly on the road, you shudder to think what the situation must be like in Winterhaven."
Or you could just mention, "As you loot the kobold bodies, the sun begins sinking below the horizon. It won't be long before the beasts that prowl this wilderness are attracted by the fresh meat. You should probably be moving on."
 After 30 years, the designers of D&D should be able to run a top class RPG even while asleep. Why are beginners' mistakes like this being presented to new DMs as if they're useful advice?
 Although the players are given some over-arching quests that provide a reason to travel to Winterhaven in the first place, there's no particular sense of urgency attached to any of them. Why isn't a clear and immediate motivation to continue to Winterhaven presented explicitly in the module?