The main intent with the footer link is to try acquire additional clients, so just having it in a blog post can potentially cost you business. However, you do have to worry about over-optimizing yourself due to all the links with exact match anchor text. There was actually a different blog post about this recently:
http://searchenginewatch.com/article/2239260/Using-Footer-Links-to-Diversify-Your-Backlink-Profile
In the article it suggested creating a page on your website specifically about this project. This ensures that you link to a relevant page, in Google's eyes, as well as a relevant page for anyone that is interested in your services. The blog also suggests no-following all of the links minus the one on the home page. That way you still get a decent amount of link juice, but don't have to worry about a site-wide link.