Hybrids are slow to enter the market because they do not have enough benefits to justify choosing one over a regular car. Despite what you read about the better gas mileage, you only get it if your doing a lot of braking, idling, etc. If your normal workday commute is 50Mhp on the highway for 1/2 hour each way every day, you won't see enough gas savings to bother with. And in the US espically on the West Coast, we have a lot of highways.
If the hybrids were cheaper than regular cars everyone would be buying them. But they are priced the same, or more expensive. The hybrid's biggest attraction is gas savings - but the very segment that is most interested in gas savings are the economy car hunters, who are very concerned with total car expenses, and that includes repair expenses. There is not enough time out there to get a feel for what typical failures are going to be, and how much they will cost to fix.
Ted