2-D vs 3-D Style Differences
For many games, going 2D or 3D will define it more than the actual storyline, graphics, characters, etc. In some cases it is seen as the natural evolution to go the "next step" and keep with the times and vastness that a 3-D game can offer. We've seen enough of these games fail to conclude this is not the general rule.
Games like Contra have gone full circle. The early games in the series were considered classic 2-D sidescrollers, then they came out with the 3-D version on the PS1 - which failed miserably, then bringing it back to it's uber-difficult but fun 2-D incarnation on the PS2. I think they failed to take into account the controls necessary in a game like that.
One of the biggest drawbacks of 3-D games is judging distances, performing quick and accurate actions (such as jumping onto moving platforms or aiming at/attacking enemies). It benefits from a wider environment, greater choices, different types of graphics...it can be a drawback too, if it takes too long to move your character you may not care that you have all that space.
2-D is usually done with the sprites, so the animation can appear a bit crisper - and also does the cartoony look much much better. It doesn't allow for as much exploration, though games like Metroid and Castlevania: Symphony of the Night show that enough variation can be put in to make it a labyrinth to explore in its own right. But many times the one-hit deaths for your character can be annoying if you have no options in moving from the approaching hail of bullets/fireballs/explosions/whatever.
I like both, but in general I prefer fighting/shooting games (excluding FPS shooters) to go the 2-D route. For Fighting games it focuses on the action (though a reduction in dodge ability is a plus and a minus) and makes more difficult combos not impossible to execute. Roleplaying/Adventure games are better with the 3-D route, gives you more to explore. Storyline over graphics usually takes precedence so if not everything is crisp or smooth it isn't noticed as much.
There are exceptions to every rule though, games that you wish had not gone one route over the other.
Games like Contra have gone full circle. The early games in the series were considered classic 2-D sidescrollers, then they came out with the 3-D version on the PS1 - which failed miserably, then bringing it back to it's uber-difficult but fun 2-D incarnation on the PS2. I think they failed to take into account the controls necessary in a game like that.
One of the biggest drawbacks of 3-D games is judging distances, performing quick and accurate actions (such as jumping onto moving platforms or aiming at/attacking enemies). It benefits from a wider environment, greater choices, different types of graphics...it can be a drawback too, if it takes too long to move your character you may not care that you have all that space.
2-D is usually done with the sprites, so the animation can appear a bit crisper - and also does the cartoony look much much better. It doesn't allow for as much exploration, though games like Metroid and Castlevania: Symphony of the Night show that enough variation can be put in to make it a labyrinth to explore in its own right. But many times the one-hit deaths for your character can be annoying if you have no options in moving from the approaching hail of bullets/fireballs/explosions/whatever.
I like both, but in general I prefer fighting/shooting games (excluding FPS shooters) to go the 2-D route. For Fighting games it focuses on the action (though a reduction in dodge ability is a plus and a minus) and makes more difficult combos not impossible to execute. Roleplaying/Adventure games are better with the 3-D route, gives you more to explore. Storyline over graphics usually takes precedence so if not everything is crisp or smooth it isn't noticed as much.
There are exceptions to every rule though, games that you wish had not gone one route over the other.