Is there any stronger marketing message than a testimonial? Probably not. Companies like Angie’s List and organizations like the Word of Mouth Marketing Association will tell you that testimonials are peerless. If a couple of Indianapolis residents have their way, cities like ours may soon agree.

A few months ago, Pat Coyle, Director of Database Marketing for the Indianapolis Colts, read with interest an article in the IBJ about the recent branding efforts being undertaken by several groups across the city. The idea was to pool their resources, focus on one branding concept, and get a better response by having all of the groups singing the same tune. At the time of the article, the group had just rejected “The New Midwest” as a possible candidate and had retreated to the drawing board to come up with something new.

The concept was intriguing to Coyle, who rightly deduced that Colts.com and the city were very likely trying to communicate with the same type of person: 40-something professionals – many in creative fields – people who fit neatly into the “lifelong learner” category.

Pat woke up a few days later with the phrase “I Choose Indy” on his mind. While he thought this nicely encapsulated the whole concept, it didn’t appear likely to be adopted by the groups at large. Still, Coyle thought there were opportunities available to make a difference. A few days later, the breakthrough idea arrived.

“I had been reading a book about blogging and thinking about how blogs provide faster communication and are indexed more often by search engines,” Coyle told me. “Then I thought, ‘wouldn’t it be cool to have a blog telling the stories of professional people in all fields who have chosen Indy?'” Coyle called his friend Doug Karr, a Product Manager at Exact Target (read: geek) and I Choose Indy was born.

On the site, people in all walks of life are encouraged to register, select their area of expertise, and write a post about why they choose to live, work and play in Indy. Over time, as more people register and post their entries, the site has the potential to be among the top results when someone – whether it’s an employee or an employer – searches for information about Indianapolis. Once on the site, visitors can drill down to specific industries to see why other people in their field chose Indy.

“If nothing else,” Pat says, “I thought it would be an interesting experiment in grass roots, word-of-mouth marketing. At best, I thought it had the potential to be more effective than any ad campaign.”

The site is still the early stages, but postings are beginning to mount and the site will undergo a professional design upgrade soon. The next step is yours: visit I Choose Indy, register, and tell your story. You’re words could help make this “grass roots experiment” the strongest testimonial and most powerfull marketing tool in the city’s arsenal.

In case you’re interested, here’s why I chose Indianapolis.