I have a website listed on google search. It was number one in it's
catagory. My server whent down for three days before I noticed it.
Shortly after coming back on its position went down to 15?.. my
question is, did my down time effect the position in the index? and
will it come back or is it black-balled ?

Hi kenstral,

  Good day and thanks for your question.

  First of all, I must say that you're extremely lucky that your site
hasn't been dropped from the database. I had an experience once. My
webhost shut down without any notice, and for a week I was without a
host. During this period, my site's listing totally dropped out from
the database, with not a page in the index.

  Google have a number of spiders (or crawlers) crawling through
hundreds of millions of webpages. Normally, 5-10 spiders crawl a site
and the pages are then indexes. It is highly likely that your downtime
affected only a few spiders, and the rest of the spiders crawled
through your pages when your site was back up, resulting in only a
partial spidering of your site. Hence, the drop in ranking.

  Your website will be back at the top during the next index rebuild
(as was the case with my site). However, this could take upto a month.
There is no need to worry. Your site isn't back-balled. The only way
Google penalizes websites is if they are caught using stealthy
techniques to boos their search engine ranking, such as cloaking.

  I hope this answers your question. If you have any clarifications,
then please don't hesitate to ask, else, feel free to rate this
answer.

  Thank you for using this service and have a nice day.

Warm Regards,
Aditya2K

great answer !!!