Race Walk versus Fitness Walk
The Dexter Ann Arbor Run home page was not very clear on the difference between the 5K Race Walk and the 5K Fitness Walk.  I emailed them looking for clarification and this is how they responded:
dxaa2001@aol.com:

The race walk involves a special technique and will be judged.  There are awards, but also judges who may disqualify you for improper technique.  It is a very special form and is an olympic event.  The fitness walk is just as it says "fitness".  All fitness walkers receive a ribbon.
In summary, if you plan on walking a 5K on race day, sign up for the Fitness Walk unless:

1.  You want to be 'judged' as you walk and risk being disqualified.
2.  You feel like this race will propel you into Sydney Summer Olympics as a Race Walker..
3.  The 8 a.m. Fitness Walk start time just isn't early enough for you and the 7:40 a.m. Race Walk time is so much more appealing.
4.  You walk exactly as shown in this graphic from the 2000 Race Walk Officiating Handbook.

Its a good thing Lynn chose the Fitness Walk instead of the Race Walk in last year's race.  This picture shows a clear violation of Acticle 2, Rule 267, Section 3 of the Official Race Walk Officiating Handbook.