exactly..even i think the same..and in addition to that i must say..i have now ordered for my site's search engine optimization and they have asked me to add link backs..so its necessary to get link backs guys for getting your site among top sites in search engine indexing..of course excessive link backs would be disadvantageous as google will be ignoring you then..

@archy..archy link back or link exchange means like i ask you to include my blog/sites link on your blog somewhere in exchange for your blog's link in mine..