The Good: Beautiful, slick presentation; drawing random cards and expanding the collection is a blast; assynchronous multiplyer is a good fit
The Bad: ESRB could put a "Game Dev Mischief" label on it
More than simply delivering an addictive match-3 experience--which it arguably does with its decent share of twists--Marvel Puzzle Quest appeals directly to childhood nostalgia in two fronts: offering the overwheelming feeling of being an uncanny/amazing/incredible/etc superhero and, if it wasn't enough, collecting stuff.
The concept isn't devilish in itself: as you play through the levels you're handed random (to some extent) cards for money, energy, battle boosts and--specially--characters. The later are a delight to find and use in battles since they vary in power/abilities an can appear in several iterations (classic, modern, dark, etc) eventually providing treats to any Marvel fan.
The problem is: the game starts as free-to-play, but is crafted to fry the player the next corner. From the beginning there's little room to accomodate the newly unlocked characters and expanding the roster will cost the so-called Hero Points. Those can be earned after some tough battles, but only if you're lucky enough to draw 'em--chances are much higher for consolation prizes instead. And here's where the devious design come into play: hero cards expire in one week--about the time you'll find yourself desperate to avoid letting a particularly wanted character slip away; fighters take time to heal after battles, and evolving them will bring power as much as longer cooltimes to get ready for the next try--again, leading you to consume Health Packs faster than the game drops 'em; some levels are locked to specific characters, and if you don't have 'em yet simply making a real-money purchase will grow tempting.
And there's much more. The entire game flow--with its beautiful menus and all--is like a big quicksand funnel ready to drag the prey down.
It is possible to play through it without spending a dime--like I did for three weeks or so until beating the main Story mode. But it will cost time for grinding and trying your luck, and it's up to you to decide which resource--time or money--is the most valuable.