Any, really noticeable, load screens. I don't really get those, because I play games exclusively on PC.
The load screens in Dragon Age: Origins were quite annoying. And more specifically: when moving from a larger area to a much smaller one and vice versa, like going to a building in Denerim.
It's an obvious screw-up by the makers, as the larger area could easily be kept somehow preloaded, as you won't be spending long times inside the buildings and those could just as well be included within the same area. Instead it's like moving to a completely different village. And the "load screen" is just pitch black silence for a few seconds, so it feels all that much longer.
FIFA 2011 has absolutely the best load screens with the 1-on-1 against the goalie scenario, that you can play. It's one of the best things in that game.
Longer load screens should allow to do something small, and not necessarily even anything that interesting, while it's loading. But by no means should it add noticeably to the loading time.