I think the voices in video games are a good addition if they're done well, like in KH games, for example. I couldn't really imagine playing RTS games like C&C or StarCraft without the units responding when I click at them. I also think the version of "Day of the Tentacle" with voices was better than the one without voices.

The voices tend to get annoying when the voice acting is weak, though. For example, I have mixed feelings about FFX's voice acting. On one hand, the voice acting was done well for Rikku and Auron (IMHO), but on the other hand, I thought the voice acting for Tidus, Yuna and Seymour was quite lousy.