Hmmm. That's a tough call.
The story you've hinted at has a Matrix/Resident Evil movies feel to it. I can see how it would be difficult to continue without voices based on the end of the latest Tetris'd.
I think what your fans keep coming back for is really the style of the Tetris'd videos. Stay true to that, and they'll be happy, voices or not.
If you do decide on adding voices, I hope you'll consider me! Here's my demo:
<a href="http://www.newgrounds.com/audio/listen/418899">http://www.newgrounds.com/audio/liste n/418899</a>
I can also help you write and brainstorm ideas on where to take the story. Just shoot me a PM if you decide you want help.
- Matt
PiGPEN
>Game about dodging tetris blocks.
>Add a story.
Are you retarded?
KobraEditing
It was an animation first and there's already a story. A weak one. This is why I'm asking if people want a better one or just an action packed finish.