Note the cheer-up message. There is a variety of them in the game, popping up every now and then after a particularly successful combo and fading out of the way.

Blue rings are the only trace of what was a bunch of same-color blocks just a split second ago. Nice combo!

Mmmm, Bomb powerup. The screen shudders, debris flying across the playfield; a sizeable chunk of blocks gets obliterated... If this is not awesome, nothing is.

The trail of Chainsaw. You might be able to discern that this powerup has just removed 5 blocks.