There is a major inherent danger that hasn't been touched upon.
Because you are taking about reciprocal links, you have the giving away as well as the receiving.
Many companies will give you a link in exchange for one on their site. The problem lies in the fact that you invariably get excited by the Page Rank of a site, without looking at the
PR of the page where the link is going to be. Often the "links" page is penalised for giving away a lot of it's
PR in outbound links. Even worse, some sharks will keep the links page in isolation from the rest of the site, so they might say "we have a Page Rank of 7", but if their is no links to that page from the PR3 links page buried in the dungeon.......
We undertake a lot of work for clients in link building as part of overall traffic building strategies. More often than not when we get a link it's an inbound one that is not reciprocated and it's usually of good quality and an active link rather than just one to chalk up another notch on the link popularity belt.
The reason for that is because we are the 3rd party in the equation and there is normally 2 or 3 reasons and benefits to the link being given and we are very persistent. Our average "attempts" to get a link is well over 3 times before sites give a link and it takes a fair amount of co-ordination and follow up and a large amount of persuasion.
Is your brother up to the job ? Good links should be well rewarded. Offer him so much up front with a performance related bonus for links that deliver traffic.
Chose the link text, page, position and make it easy for the webmaster to include you. If you intend to reciprocate, do it first, tell them you have placed a link on your site already, if they click on the hyperlink in your e-mail it's a boost to your traffic figures anyway. That way even if they decline the link, if you do enough of them then you'll win some in the end.
Jim Banks
Web Diversity Limited
www.webdiversity.co.uk