If your site has pr of at least 1 then this is by far the best seo tactic: exchanging links. Google is primarily based on links to your site. The higher quality (ie. pr) the link, the better! You want those high pr links, if you get those links to your page you will rank very good. Likewise, since your site has pr don't give away your link juice for free by linking to sites who don't return the favor. What I mean by this is that your page (with pr) has a high value to other webmasters because they obviously want you to link to their site so they can rank better. Likewise, you want those other webmaster's high pr pages to link to your site so you can rank better. To take advantage of this you simply do link exchanges. You place other webmasters links on your page and the other webmaster will link to your site with a different site of theirs. Its a win-win situation. To better leverage your site, you should create blogs and try to get those blogs to have pr as well. Once they have pr you simply do link exchange and have the other webmaster link to your site. Using this tactic, with sufficient time, you can rank for ANY keyword. Yes, even keywords that have hundred of millions of results or even billions of results. Obviously the more results the more links you have to get but anything can be accomplished with time. Also if your site has no pr then you have to do basic link building like forum signatures, article submission, directory submission so on so forth. No one will want to do exchange links with a pr NA or pr 0 site.
that's a very good advice, noone wants to swap with pr0 sites and I see so many people just trying to exchange this...
Reciprocal linking still has some value but I would try to do it in a sensible way. Rather than having reciprocal links pages with hundreds of links which are easily spotted by any algorithm and no doubt seen as worthless, try to do it via blog posts. Recip linking should not be just about trying to accrue page rank. It should be more about building a social circle and partnerships around your site and building brand awareness. Better to take the time and effort to create something of value and partner with another blog and do a guest post. You can then return the favour later down the road. If the blog has good traffic you will get far more traffic than you ever will from a recip link embedded between hundreds of other links. The other good thing about this is that "contextual" links are very powerful and given a lot of weight by Google and the other engines. So, by getting a natural link within a blog post, you will also get a good organic SEO boost. Now. Isn't that a better idea?