Right now I am getting pretty good traffic from Google. If I forward my subdomain to a new domain, which I purchased from an auction, would I lose anything? Also, the new domain is 3 years old and has a pr of 0, my subdomain is a month old and has a pr of 2, will it benefit me at all?
Only if the new domain focussed on a theme similar to the theme on your subdomain. If this is the case, do a 301 redirect from the sub to the new. Usually the change on Google goes very smooth and your new domain will rank very fast where your sub has been. But if the new one had a completely different focus than your sub has, you will loose your rankings and have to start from 0 (zero) again.