I was short on time and only marinaded the chicken for about 30 minutes and it still was very flavorful. I added an additional tablespoon of red vinegar. After broiling, the syrup gave it a nice crispy caramelized coating.
The only change I made was to omit salt and pepper, and reduce the olive oil to 3 tablespoons. The chicken breasts were in the marinade overnight. This is not too sweet, just a hint. It's yummy! Thanks Oolala :)