There's a lot of interest and also a lot of questions when it comes to hybrids now adays so I found this site that has some pretty good information from a BC Govt fleet of 64, 2001 Toyota Prius.

2001 Toyota Prius
The detailed maintenance/repair records for the 64 Toyota Prius in the BC Government Fleet were analyzed and the following conclusions can be made from this data:

• The average maintenance cost for the 64 vehicles was $1268. Based on the 2.57 million kilometres (Average of 40,293 km per vehicle) traveled, the maintenance costs were an average of $.0336 per kilometre. Note: Two vehicles had charges for accident repairs totaling $10,630 and $7,097. These costs were removed from the average maintenance/repair costs to more fairly represent typical maintenance costs.
• The remainder of the costs were related to normal type costs for items such as winter tires, preventative maintenance, and windshield repairs.
• There were no costs identified that were specific to the hybrid components of the vehicles.

There's a lot more info about this fleet along with all kinds info about hybrids in general
The Hybrid Experience Project