As Lonman mentioned, glucose is more rapidly absorbed in the GI and tends to elicit higher blood glucose and insulin responses. This makes glucose ingestion ideal for situations where rapid digestion or energy provision is required (during exercise, during a hypoglycemic episode, post exercise) but not so great for the remainder of the day when stable blood sugar and insulin are desirable. Glucose is found as a monosaccharide in fruits, vegetables, and honey as well as many manufactured sports drinks. Most blood glucose doesn't come from glucose ingestion but from other dietary carbohydrates that are eventually broken down into glucose.
Fructose, on the other hand, is metabolized differently due to its structure. In the liver, fructose is metabolized and can replenish glycogen (liver only) or can form triglycerides. Due to the fact that fructose doesn't cause a substantial rise in blood sugar (it's too busy filling liver glycogen stores and creating triglycerides), it doesn't stimulate insulin secretion to any large extent.
Now, the great debate among nutritionists has been whether the low insulin response is enough to outweigh the inevitable formation of some triglycerides. In my opinion, the best answer is that it all depends on how much fructose you ingest. With a very high daily consumption of fructose (from lots of fruit, but even from the more lipogenic high fructose corn syrup and from sucrose, which is in fact, a glucose and a fructose joined together), the lipogenic effects should probably be considered.
However, a moderate daily intake of fructose, especially from fruits, is encouraged. Just be sure not to consume fructose around exercise time. It has been shown time and time again to cause GI distress, increase ratings of exertion, and cause higher serum cortisol levels when consumed in conjunction with exercise. Fructose is found naturally in many fruits, berries and honey (foods that I highly encourage consumption of) as well as some dietary supplements, but in Western society most people get fructose from processed foods containing high fructose corn syrup.