Reciprocal Linking Dangers:

In the 'good old days' Google and most other search engines used links to determine a websites reputation. For example 1 link = 1 vote of confidence.
A site's ranking in Google search results was and still is partly based on analysis of those sites that link to it. Link-based analysis is an extremely useful way of measuring a site's value, and has greatly improved the quality of web search. Both the quantity and, more importantly, the quality of links count towards this rating. 

However, some SEOs and webmasters engage in the practice of swapping, sharing, buying and selling links, often disregarding the quality of the links, the sources, and the long-term impact it will have on their sites. Buying links in order to improve a site’s ranking is in violation of Google's webmaster guidelines and can negatively impact a site's ranking in search results. 

Google works hard (very hard) to ensure that it fully discounts links intended to manipulate search engine results, such as link exchanges and purchased links.

Google requests, If you see a site that is buying or selling links, let them know. They will use your information to improve their algorithmic detection.

Some site owners attempt to "buy PageRank™" in the form of paid links to their sites. There are even websites whose sole business is to sell links. Buying links to improve your websites PageRank also violates Googles quality guidelines, and you seriously risk being BANNED from the Google Index.

What does this mean?
It means Google and other search engines dislike websites which attempt to manipulate natural listing by employing unfair techniques. If you are caught participating, you WILL be banned from Google. Dare you take this risk?

So what is the answer?
It's not rocket science. Simply make sure your website is presented correctly, sometimes called 'Search Engine Optimisation' or 'SEO'.  This involves creating clearly written good quality content which represents your main keyword phrases. 

Link to this website:
If you found this article interesting, then why not link to this website so others can read it too?
I prefer you to link with the abbreviation 'SEO' and this is a clear demonstration of how links should really work :)