Pitching yeast

I am curious about pitching dry yeast vs. live yeast--it seems like live yeast from dry package would be a serious contamination worry...is there a benifit to live yeast being introduced? In my beer brewing I always pitch dry and have never had a problem, does anyone know about this, specifically when it comes to cider?

Also, what is the difference between using beer/wine/cider yeast in my cider? Flavor? I am toally in the dark about all the different yeast..thanks for any guidance you can/care to give

Dry yeast is also alive, just dormant. Liquid yeasts come in more varieties, but you only get about 1/10th the cells. http://www.oregonbrewcrew.com/ has an article called the Great Mead Experiment, where they compare yeasts in fermenting mead. It's all about flavor.

I used dry/packet yeasts for about 1 1/2 years before switching to liquid yeast. There was a dramatic improvement in flavour and increase in my wifes happiness, there is no way I'd go back to dry yeast. I've been told by my local Home brew shop that different yeasts will "strip out" different amounts of flavours. I'm not sure if that is the best way to describe it but you get the gist?
cheers