duplicate content - G sandbox?

is this a myth or does G really punish a site for having duplicate content?
if you do get punished, how long does this last?
How about spun articles, whats the minimum for a spun article 20-30-50%?

How about back links, getting too many too soon..is there a penalty?

any help would be great...

The only punishment that you get is a low position in the SERPs

Just my 2c here - played with UAW on one of my lab blogs - normally showing PR0 (no promotion, no ads etc). Sort of ignored it for a couple of days (less than 2 weeks I think). On checking again, it had about 12-15 articles from UAW of miserable quality (written by some poor Chinese sods and / or script-spun imho) and not showing PR at all (grey bar, probably sandboxed). I took that sh** out (checked copyscape on one, duplication big time) and put some articlebase posts in place. Back to PR0 after a week. Take it as you want - in my opinion, either high duplication (on sandboxed blogs?) or UAW flagged with Google must have been responsible for that.

thanks~~~~~

The duplicate content punishment is a myth in my honest opinion. The only time Google will penalize a site for duplicate content is if you have it on the same site.

If you have the same content on multiple sites, you don't have anything to worry about really.

As far as being punished, Google's not gonna come knocking at your door. You will just be ranked lower in the SERPs or your rankings will drop if you are already ranked.