Last year's inaugural event was a great success and offered MX and HS racers a track that was not only completely different than anything in the Midwest, but also a great compromise for both riding styles.
For this year, the track layout has changed to offer more variety with woods sections, as well as split-sections that give the rider an option (once again based on riding styles and what they're most comfortable with). The only thing that hasn't changed is the 35 minute motos and the big uphill section that the race has become known for. For those of you who don't know, the uphill section is 3/10 of a mile long and is the largest vertical distance in the lower peninsula. It is also likely one of the only motocross tracks where you can tap-out your 450 for the good part of 20 seconds going up hill.
Here's a few links for more information:
Last year's Racer X Report (includes photos and an awesome helmet cam video: link
One more thing, if you have received the most recent issue (October) of Dirt Rider Magazine, check out page 97, where the GLGP received the 3rd place honor of "The 10 Best Off-Road Events In The North"