4E was absolutely, 100% built from the ground up to be 'encounter-based'. It's impossible to read the rule books and come to any other conclusion, since every action PCs can take, every special ability they have, all revolve around how often they can do said cool thing in the course of a day.

This makes 4E combat tremendously exciting, but the offset to that is that everything else seems lackluster by default, because a combat encounter is the only time you're generally using those amazing powers. While you need a competent DM to have any fun in any version of the game, you REALLY need a DM who knows their stuff to adjudicate combat in a 4E setting.

5E combat, for me, has so far been a ton of fun. Every encounter usually plays out a bit differently than the one before (which is good, because combat in 3E often revolved around players using the same 2-3 feats repeatedly during every fight, especially Cleave, Power Attack, and Dodge). Even the novice players have enough choices by the time they hit level 3 that there's something different to do and new to try. And I love that so much.

I just wish more of 4E's combat mechanics had survived the transition to the new rule set, because they look so damn fun. :)