I like cut-scenes on these premises:
Skippable. If a cut-scene is necessary game mechanic, ie necessary to see to be able to overcome tasks later on, make them unskippable the first watching and skippable after that.
Short. A good cut-scene does not interrupt game-play for more than 30 seconds. Absolute maximum is 2 minutes, after that, it all goes stale. (Intro movies that set the mood for certain settings are excused, if barely.)
Serves a purpose. A cut-scene without a point should be avoided.
Use in-game engine graphics. Pre-rendered works for intro's and outro's, but when in game, I want to see my character interact with the world the way I set him up in regards to weapon, armour, clothing,hairstyles and what not.
That is all I think.