Seo and Short URL System

i want to know that some people commenting their website url's via short url like tiny.cc
and bit.Ly.....

if we use short link via blog commenting or forum posting and forum signature or in social bookmarking site, is it help in seo and are these short link

counted as backlinks?

regards

great post thanks for sharing here

i feel it is better to use the original links instead of tiny/short urls in Blogs and Forums. Where as in social media marketing, it is useful to go with short urls making the user land on the page.