I think 3 is cool, but on the same time It would be cool to have more episodes

maybe 5... But at the same time I wonder if more episodes won't diminish the quality... Perhaps the show is better the way it is, even if it seems too short :)

Well having only three episodes gives them more time to make them how they want them and to get them up to quality. And remember they're each 90 minutes long so they're film length episodes which you don't see everyday. If they had more than three episodes I think they would have to be shorter and lesser quality. We need to think what would be best for the show rather than what we want.
They originally wanted to make 6 30 minute episodes, so the 3 90 minute episode are more than they where originally going to make.

Depends how they'd be made.

Think 3 eps are great, but on the other hand I like watching more of Sherlock. So I hope for a season 3.

I think it is very clear that it is because of the small number of episodes that the quality is so good. Everyone has much more time to make everything perfect, the writer's don't have to rush for example.

And that is why even though I think more would be pretty great I would also probably love the show less.

3 episodes is good because it means they put more effort into each one. I would rather have 3 longer episodes with a stunning amount of detail and work put into them than 12 or so average-quality plots.

we cant get enough of it..so please please more episodes at least 10 for each season. 3 episodes are never enough.

I wish that there were more episodes in each season. But then again each episode is like a movie so if there were more episodes then it may be harder for them to put all of their effort into it.

Quality over quantity.